The Basic Elements of Survival
The main elements of survival are Food, Fire, Shelter, Water, Navigation, and Medicine. To put these in order of priority we use the acronym PLAN. No matter where you are in the world this will never change, be it the Arctic, desert, jungle, sea, or seashore.
P - for Protection
You must ensure that you are protected from further danger, i.e. impending avalanche, forest fire, or exploding fuel. Always stay at the scene of the incident (such as a vehicle breakdown) as long as it is safe to do so and then make sure you are protected from the elements. This means making a shelter and often lighting a fire. There are several reasons why you should always stay at the scene:
1. You can utilize the wreckage for shelter, signaling, etc.
2. It's a bigger signature on the ground, making it easier to find.
3. There are probably injured people that cannot be moved.
4. By staying where you are you conserve energy.
5. Because you have booked in and out and have stayed on the route, rescue time will be minimal.
L - Location
The next step after building a shelter is to put out emergency signals. You must draw attention to your position. Do this as soon as possible to help the rescuers.
A - for Acquisition
While waiting to be rescued, look for water and food to help supplement your emergency supplies.
N - for Navigation
Good navigation will keep you on route and will often avert a survival situation. But if you find yourself stranded, always stay where you are.
You must become your own doctor and carefully monitor yourself at all times. Treat blisters as they occur; don't let them become septic. Keep an eye on your companions and deal with any unusual problems as they arise. If they are limping, falling behind, or behaving strangely, stop and treat immediately.
This is an excerpt from John 'Lofty' Wiseman's SAS Survival Handbook.