Predicament: You've been hiking for hours under a scorching sun, and the terrain looks unfamiliar. You're totally disoriented in an arid land. How will you last the night?
Lifeline: If you can't navigate back to a known place, stop moving and find a conspicuous spot to wait for rescue. Cover exposed limbs and your head with light clothing. Seek shade, or create it by throwing a sleeping bag over a tree. If water is limited, don't eat–digestion requires water. To conserve body moisture, breathe through your nose, and stay as cool as possible. Create a large X (the "need rescue" symbol) at least 5 feet long with rocks. Sit on your pack, not the hot ground. Flash a signal mirror at planes or dust clouds, which could be vehicles. As night and colder temps set in, find a warmer shelter. No caves or natural features? Dig a body-sized trench; cover it with a folded tarp or Mylar blanket. Insulate the bottom with extra clothes. Next, look for nearby water sources by searching for animal paths and digging in the outside bends of dry streams. Mosquitoes and birds are a welcome sight, as they seldom stray far from water.