There is of course a great book out there that can give you a jump start, The Ultimate Hang. I actually didn't come across it until well after I had already traversed the painful hammock learning curve. I could have avoided some VERY cold nights! But trial and error is just my style.
Feel free to use the following advice in lieu of (or in addition too!) Derek's book. I'll also sprinkle this primer with the gear and hardware I've used throughout my hammocking career.
For those who might be reading this and don't know what all the fuss is about, I should probably start with the obvious question: "Why hammock at all? What's wrong with my ground system?"
Well, probably not a thing! It's a personal preference, but there are some advantages to hangin'.
For me, most importantly, I hammock to get a good nights sleep outdoors. Try as I might, I just don't sleep well on the ground. I'm a side sleeper mainly, with broad shoulders. No matter how luxurious a sleeping pad I employ, I rotisserie all night and still wake up with acking back, shoulders, and hips. All those issues became a thing of the past when I become a "hanger".
Another advantage, which was highlighted on the very first trip I tried hammocking, is staying "high n' dry". If you've done it correctly, the only bit of your sleep and shelter system that will get wet during a downpour is your tarp. Even if you setup after (or during!) a storm. You can blissfully pack up your gear and keep it dry under the safety of your shelter while your camp mates are wallowing in the mud!
So what are the disadvantages?
Compared to a ground system, I would say that a complete hammock system is going to be (potentially) slightly more expensive, and also slightly heavier. Depending on the setup, my hammock system weighs in between 8 and 16 ounces heavier than my comparable ground system. In the summer however, my hammock setup can actually be lighter than my ground setup!
There is also the previously mentioned steep learning curve. Hammocking is inherently more complex. You have more moving parts and pieces. I think I can generally have my hammock setup just as fast as most people put together their ground system - but I've had some long setup times due to exhaustion or frozen fingers. Or sometimes the trees don't cooperate and you just can't find a good spot for a perfect "hang". In addition, a failure of your suspension or hammock itself my lead to spending an uncomfortable night on the ground.
For me, the slight disadvantages are more than blown away by all the advantages. I probably would have stopped backpacking long ago if I had stayed with ground sleeping. So far, I haven't experienced a critical failure of my system - but I have seen it happen to others.
The Anatomy of The Hang
A hammock system essentially has the same pieces as a ground system, with the hammock itself thrown in. You have your shelter, your top insulation, and your bottom insulation. We'll start with that tricky bottom insulation first.
The first time I hammocked overnight was actually in The Black Hills of South Dakota in the summer with a cheapo Byer Traveller Lite Hammock. It seemed like a perfect fit! Mild weather, lots of trees, what could possibly go wrong?
Well it wasn't bad, but I was definitely cold. I'm sure the temperature never got below 50, but with no underquilt or pad, the mild summer night and light winds most certainly chilled me. Yeah, classic noob hammocker mistake. You gotta have bottom insulation. Almost all of us have a similar story.
The next few trips after that I used my foam Z-lite sleeping pad. This was way warmer, but still not ideal. My shoulders always got cold (being pressed up against the hammock), and I found myself slipping around all night. Staying on the pad was a challenge.
Then, at long last, I discovered the miraculous invention that is the Underquilt. Hammocking has been bliss ever since. No more Cold-Butt-Syndrome. No more chilly, sleepless nights!
Underquilts have a comfort rating just like sleeping bags (and top quilts) to help you choose the one you need.
I've purchased several from Hammock Gear over the years. Their prices are good, quality top-notch, and comfort ratings are quite generous. You can get your quilt custom made exactly the way you want it.
Bottom line - never go hammocking without bottom insulation, any more than you would sleep right on the ground. No, not even in the summer! Even on hot Virginia nights, I might leave my top quilt at home, but you bet your butt I'll have an underquilt. I also can't really recommend using a pad in a hammock. Yes, it works. And plenty of people are completely happy with it. But in my humble opinion the underquilt is the only game in town.
Top Quilts/Sleeping Bags
This part is easy. Chances are, you already have a sleeping bag or two. It works just fine for hammocking! I used several more or less in "quilt mode" (i.e. unzipped and just on top of me) when I first started hanging. Eventually I starting acquiring topquilts (also from Hammock Gear) to save some weight and shed some excess bulk. You might find in the mild summer months that a bag liner is all you need. So top insulation, check!
There are a variety of tarps you can use for keeping out of the wind and rain. From a plain old nylon square tarp to one purpose built for hammocks. I started off with an ENO ProFly - cheap, durable, and easy to setup. Eventually I wanted less weight, and more coverage. Enter Cuben Fiber! I purchased a cuben tarp with doors from Hammock Gear - and it's been all I've used since. 6.4 ounces (sans cordage)!
I eventually rigged the tie-outs with 1/8" shock cord and Nite Ize Figure 9s (after trying various other methods). This makes for a rapid and easy-to-adjust setup. It also takes up any slack that might develop in your tarp due to rain, snow, or any minor adjustments you make. Combined with some fancy titanium gear from www.dutchware.com I had a lighting fast setup with minimal weight.
If you are already familiar with ground tarps for shelters - or you like cowboy camping - transitioning to sleeping under a hammock tarp is pretty easy. If you are used to more traditional tents or other fully enclosed shelters, you mind find it a little disconcerting at first. But give it some time - you might find you love the open feeling! Especially once you enjoy the other benefits, such as total lack of condensation. It's hard to beat getting gently rocked to sleep under a canopy of stars.
So which hammock to pick? There are probably hundreds if not thousands of hammock manufacturers out there. There are also multiple types. The kind I'll be talking about are gathered end hammocks. As opposed to another common type, a bridge hammock. Gathered end hammocks work by creating a nice "sag" in the middle. You get in, and then sleep diagonally - this keeps your back and legs straight. A bridge hammock is meant to be suspended tightly, and uses rods or poles at the end to keep everything taut.
Gathered end hammocks are not only lighter and cheaper, I think they are more comfortable. They are also a cinch to setup.
Like I mentioned above, I used a dirt cheap Byer Traveller Lite Hammock for years before deciding to upgrade. I wanted an even bigger (and lighter) hammock for my 6'5" frame, so I checked out Butt In A Sling. Their "Weight Weenie Micro" checked both those boxes. It also has a built in Amsteel ridgeline - something I hadn't tried before but consider a must have feature now. It not only gives you a consistent sag, it gives you a place to hang your stuff at night!
More recently I discovered Sheltowee Hammocks. They make a variety of gathered-end hammocks, but I was most interested in their Boone Hammocks. These have built in underquilts, that are still adjustable. What you get is a full coverage underquilt that is faster to deploy and much warmer then your average hammock + underquilt setup. The only sacrifice is a slightly heavier weight. Also, you can't remove the underquilt if you want to head into colder temps then normal - though you can add to it!
If you have more than one underquilt, you can double them up for bonus warmth. Just remember that to be fully effective, the insulation needs to loft fully. So don't string it up too tightly. You can double up your top-insulation in the same way!
Putting It All Together
So how do you actually get all this nonsense setup? Well, there are any number of ways - each depending on the the gear you have selected. In addition, the order I put things up varies depending on the situation.
For example, if weather is crappy, I'm obviously going to put up my tarp first so I can hang my hammock in a dry space. Otherwise, I'll generally hang my hammock first. If it's windy and cold, I'll string my tarp low and tight around my hammock. If it's hot, or just nice out and I want to have my tarp open I'll rig it up high (or not put it up at all!).
Here is an overview video I did a while back (featuring the Boone 40 hammock from Sheltowee Hammock Company). It should give you a general idea if you've never seen a hammock system in person. Then we'll break it down:
In the video, I am using Stingerz from Dutchware to string up my tarp. If you look at the bottom of his page, you'll see a close up video of how to use his Stingerz.
Now, all this fancy hardware does is allow for a fast and easy setup. It's also more convenient when you have frozen fingers. However, you can easily accomplish the same thing with any old cord and some knots if you have the inclination. Some tarps, like the ENO ProFly have built in cord and line-locks which are pretty easy. I use a combo of knots and hardware.
A continuous tarp ridgeline is another method of hanging your tarp. It allows you to easily move and center your tarp at will. Two methods to do this can be found here on Dutch's site.
Another continuous ridgeline method is to just attach your ridgeline cord to one end of your tarp with a small biner, go around one of the trees then back to the biner (forming a V shape with the tree), then continue to the other end of your tarp. Clip the ridgeline into a biner there, then continue around the other tree, form another V, then back to the last biner where you tie it off. You can use a Stingerz to make that tie off easy on one end. With this setup, you can slide the entire tarp back and forth easily to center it.
The method I use most often is to simply attach the tarp to the hammock suspension itself using amsteel prussik knots. Obviously this requires hanging the hammock first, but it's the fastest and easiest method of all. For the tarp to stay taut however, you need to nail that 30 degree angle. And you need to use shock cords on your tarp tie-outs. With care, you can even take down your hammock first in the morning if it happens to start raining. (Assuming the prussik is on your tree strap and not your whoopie sling).
However you hang the tarp, you will generally need 4 stakes to then tie out the bottom corners. Some tarps have doors as well (flaps really) that you will need to secure with more stakes (or just tie them back to the tarp if you want airflow). I use the classic UL staple: the titanium hook stake.
201 level tip - I rarely end up using all my stakes. The tie out setup utilizing the Figure 9's allows you to easily loop around conveniently located trees, brush, logs, rocks, etc.
Hanging the hammock itself is probably the part that takes the longest to master. Derek (from the Ultimate Hang) probably describes it best, but here is the gist of it:
1) Find two trees at least between 12' and 20' apart (or whatever you determine your rigs min and max distance to be - your height is a factor!). You can gauge this in the wild by pacing it off. The average span of a normal walking step is roughly 3 feet.
2) Based on the trees separation, put your tree slings/huggers/traps around both trees. For example, for me and my setup, I know for trees that are 12 feet apart I need my straps to be at chin height. For trees that are 18' apart I need to be about 2 feet above my head.
3) Attach one end of the hammock to one strap, un-roll/bag/bunch your hammock, and attach the other end to the other tree. Verify you have roughly a 30 degree angle between your hammock suspension line and the tree using the "thumb and forefinger" method: If you stand next to the tree, and put your hand out with your palm facing you, just stick your thumb straight up and your forefinger straight out - that angle between the tip of your thumb and finger is just about exactly 30 degrees. Adjust the height of your tree straps and the length of your suspension to the hammock to match.
4) Attach your underquilt to the hammock.
5) Throw your topquilt into the hammock.
6) Get in (slowly!) to make sure your attachments are all good. Sleep!
Optionally, you may like a pillow. Sometimes I use one, sometimes not. My neck has funky issues so sometimes I need the extra support.
Hammock hanging nitty gritty: I prefer to use tree straps (just simple climbing webbing that is about 5 to 6 feet in length) + whoopie slings (if you are the DIY sort, they are actually quite easy to make. Get some Amsteel and fire up Youtube).
One end of my tree straps have a Dutchware strap hook on the end. I wrap the strap around the tree, and hook it, leaving the excess hanging down. Then I take the eyelet from my whoopie sling (which is attached directly to my hammock) and tie it to my strap with a Becket Hitch (modified with a slip knot for easy removal).
This is the lightest suspension method I have found that also allows for easy adjustment. It's also very fast to put up and take down. However, you can use just about anything you want that will take the weight. I even tried paracord once. FYI - it's terrible, stretches too much and binds too easily. You can also just have your tree straps continue all the way from the tree to your hammock for a dirt simple approach (most off the shelf hammock systems work this way). Play around with different methods, putting it together and taking it down, until you find the method you prefer.
I would recommend NOT just heading out into the wild and figuring it all out the first time you decide to overnight in a hammock. Sure, you can probably make it work, but fumbling around and/or finding out you are missing something would be annoying.
If you are going into bug season, consider adding a bug net like the Buginator from BIAS. Some hammocks have a built in bug net as well. Or simple wear a headnet if most of your body will be covered up anyway. You might get some ants crawling on you if your tree selection is unlucky.
Other additional gear to consider: Weathershields. I've experimented with these some, but find I rarely need them. Essentially they are an additional barrier that goes outside of your underquilt to stop wind and moisture. This can be a big help when dealing with crosswinds. Keep in mind though if you use a totally waterproof fabric, you will get condensation buildup on the underside of your underquilt from your bodies perspiration.
A recent item from Thermorest could be the holy-grail of barriers however: The Slacker Hammock Warmer. I just received my yesterday, expect a review soon!
I hope this rapid fire primer gives you some ideas to try out and saves you some aggravation! When learning to hammock, experimentation is the name of the game. You will learn something new the first dozen times you go for an overnight hang.
Have some questions? Need more details or more info? Let me know! I'm happy to expand on this. Undoubtedly there are things I've forgotten to mention, and I don't want you to be stuck as a ground dweller due to lack of information!
Sheltowee Boone 40: http://www.sheltoweehammockcompany.com/hammocks/boone-40
Sheltowee Boone 20: http://www.sheltoweehammockcompany.com/hammocks/boone-20-hammock
BIAS Weight Weenie Micro: http://www.buttinasling.com/wewemi.html
Byer Traveller Lite: http://amzn.to/1XjvWfe
HG Winter Palace: http://www.hammockgear.com/tarp-cf3-winter-palace/
HG Standard Tarp with Doors: http://www.hammockgear.com/standard-cuben-fiber-tarp-with-doors/
EnoPro Fly: http://amzn.to/1K1uI6a
Zpacks Cuben Hammock Tarps: http://www.zpacks.com/shelter/hammock_tarps.shtml
Warbonnect Superfly: https://www.warbonnetoutdoors.com/product/superfly/
Ultralight Stakes: http://www.zpacks.com/accessories/stakes.shtml
Nite Ize Figure 9's (mini): http://amzn.to/1K1uX1b
Top and bottom quilts from HG: http://www.hammockgear.com/down-quilts/
BIAS Buginator: http://www.buttinasling.com/bbu.html
Headnet: http://amzn.to/1osZn2EHammock Warmer: http://amzn.to/1ot0249
Climbing webbing: http://amzn.to/1ot0Cif