If you have the equipment, training and experience, spending a night in very cold places like Antarctica, Patagonia or Alaska is relatively easy, albeit it will never be a routine thing. But if you are suddenly confronted with an emergency situation, you will have to take action; here you have some tips.
First of all, you should not fall asleep. When people begin to suffer hypothermia, different parts of the body are disconnected from the brain much in the same part as when we go to sleep. The sensation of numbness is the same, but it is very dangerous: if you fall asleep in such conditions, you may never wake up again. Fight your desire to sleep! You can do it later, when the sun rises or conditions improve.
You should take off anything too tight: such clothes or accessories may impede normal blood circulation, thus favoring frostbite. If you are wearing things too tight, that may also cause discomfort and will certainly limit your movements, something that in a survival situation is not advisable, anyway.
Find or make a shelter to isolate yourself from the environment and weather conditions; that will help you a lot and it is not exaggerated to say your odds of surviving will double if you find somewhere to stay, or you make it yourself. Shelter construction is a very valuable skill in such situations.
Once you have a shelter, make a fire and take measures to conserve heath using blankets, clothes, plastic sheets, newspapers or whatever you can find. Inside a vehicle that has suffered an accident there are lots of usable things like the carpets and fabrics used to finish the interior, the leather of the seats and so on.
You should then take off all your moist or wet clothes; by wearing them you will suffer a tremendous loss of energy. You can dry up them using the fire you have just started, Donít use the resources of your own body.
If you have company, even if it is an animal, stay together; sled dogs and sheep will do this anyway. Isolate the soil by using plastic, paper or fabric, seek a comfortable position and cover all your body as well as your companions with Ė if possible Ė more than one layer of blankets. If you donít have them, use ponchos, plastic sheets or whatever you have.
Keep your spirits high by telling stories and jokes, and never drink alcohol, smoke or use drugs. All such substances may give you a better sensation, but one consequence of their use is that the pores of your skin will tend to open and your body will indeed irradiate more heath to the exterior.