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When you are lost in the woods, the sky is starting to look cloudy, and its getting cold, it just might be a good idea to build something you can stay warm in for a night.
Know that there is nearly always a way to build a shelter in the wilderness, and that it is not very hard to do. If it is night, don't move from where you are. It is very easy to lose yourself in the dark, and being separated from the area you do know can be even more frightening. Find an area clear of large rocks, roots, and especially ditches. Building your shelter in a ditch is a good way to stay out of the wind, but rain might make you wish you had dealt with a light breeze. It is also dangerous if you are in region prone to flash-flooding, so keep out of ditches.
Find a tree, boulder, rock face, or other large object to be the base for your shelter. It should be tall enough for you to crouch behind, and wide enough to accommodate your resting body.
Begin gathering wood. It is your most important survival tool. You will use it for your fire, your shelter and hopefully for making some traps for animals. Get anything you can find.
Starting with the larger pieces of wood you have collected, lean them against your object. As you are left with smaller and smaller sticks, start slanting them across the larger ones to avoid gaps. (Bear in mind that some gaps are okay.) Use enough sticks to make sure there are no holes; otherwise it will be hard to cover these with leaves. Do not forget to leave an entrance/exit hole
Make your shelter wind and waterproof. There are two ways of doing this. If you are in the snow, pile snow up around it. Of course, if it hasn't begun to snow yet, you can't do that. Instead, cover your shelter with leaves. First dry leaves, then wet muddy leaves if you can get them. This will keep your shelter insulated, and stop it from falling apart. Lay sticks on top of the leaves so that they don't blow away with the first breeze.
If you have time before dark, start a fire. For a good survival fire, find a somewhat large downed tree, and feed it through a fire pit as it burns. It is easy and long lasting.
A lean-to is an average and easy to make shelter, put a cross beam in betweeen two trees approx. 6-8 feet apart. Lay some sticks on a downward angle and dig them slightly into the ground to avoid movement and sliding from the base of the sticks. Take spruce bows and poke them downward into the sticks starting from the top. Walls optional and always build a fire in the front of your camp with charcoal.
If you are in a jungle, keeping you self up from the ground is a MUST, since the insects below will have nasty bites and you may catch deadly diseases. Have a moquito net and if you are not able to, find a plant that may act as a substitute repeller
Don't wander too far from your shelter and wait for rescuers to reach you. Save your energy by keeping in one place.
Don't build your fire too close to your stick shelter in case the sparks ignite it.
Always stay at least a couple feet from the fire. The minimum is 6 feet.
From
http://www.wikihow.com/Build-a-Survival-Shelter-in-a-Wooded-Area
