BASICS
A healthy human can survive for several weeks without food, and several days without water, but in many cases only several hours without proper shelter from the elements. Evaluate the weather for where you are, and to what extremes it may go. Shelter from the elements or a fire may well be your first priority. There are multiple items in a decent survival kit to help you build a shelter or a fire. For shelter, a clear plastic painter’s tarp or a survival blanket can help immensely. A survival blanket can also help to reflect the warmth from a fire.
Be careful not to damage any waterproof piece of gear. Example: instead of poking holes in a tarp to tie it off, push a small pebble up from under the tarp, and tie off around it (See Construction Notes below). Try using rocks instead of stakes to hold down corners, etc etc. Getting a good night’s sleep will make everything easier on you. Try to build as good a shelter and bed as you can. The extra time and effort will pay off. Use everything you can think of for insulation. Crawling inside a big pile of leaves or pine needles is actually pretty warm and comfortable (do not attempt this near a fire !!). A large pile of fresh pine sprigs is not only a springy mattress, but is good insulation from the ground.
There are LOTS of shelter materials and types. Any survival manual will teach you about most of these. The general rule for a survival shelter is that it is not much bigger than you are (just enough room to lie down). This allows your body heat to keep it, if not warm, at least warmer than the ambient temperature. I won't go in depth telling you how to crawl under a fir tree during a blizzard. I am sticking to a few basic favorites.
A FEW SHELTER TYPES
TARP SHELTERS - Probably the quickest and most basic shelters you can build. These can be set up in under 5 minutes using materials listed in my Survival Kit.
DUGOUT SHELTER - My favorite shelter type is the Dugout Shelter, which is sometimes called a "Sniper Hole".
DEBRIS HUT SHELTERS - One of the most basic and versatile shelter types. These can be made from many different materials.
HILLSIDE SHELTER - This shelter is quite elaborate, and takes longer to construct. If you have some time and energy, this one is pretty decent as it has an internal fireplace.
BEWARE OF IDIOTS
While building this site, I surfed around the net to see what others had written, and I noticed a big "green" trend amongst some of the writing. While it may be great advice for a site about camping to stress low environmental impact, the environment should be your LAST concern in a survival situation. You will be living at odds with it. The environment is what will KILL YOU.
One granola headed idiot out there had stressed that the roofing and insulation for his shelters and all the bedding should be dead material. He was obviously worried that someone might kill some plants... I say fuck the plants. Kill, hack, slash and bash. Do whatever needs to be done to stay alive. I hope nobody burns alive in one of his "Bonghead Bonfire Shelters" (my name for them).
Use your head as your primary weapon AGAINST nature. There's not an animal out there that gives a rat's ass about nature or the environment. Just look at what a beaver does to local environments. Does the beaver worry that the trees were alive? In a survival situation, your concern is that YOU survive... you are the animal... everything else is potential food or materials.... and I mean everything.
FM 21-76 US ARMY SURVIVAL MANUAL
I will add to this page as often as I have time, but if you want the original be-all and end-all source of survival information, it is the FM 21-76 US ARMY SURVIVAL MANUAL. I have crunched it all into an MS Word Document. I abridged it only by removing the Appendixes from the end. It is 233 full size pages in all, and the overall file size is about 2.5Mb, so it is relatively easy to download. Whereas your tax dollars paid for it already, please feel free to distribute it as you see fit. Simply RIGHT CLICK HERE and select "Save As" to Download.
Don't have MS Word? They give away the viewer for free HERE