It should be noted that each layer in the system traps air and therefore insulates. Multiple thinner layers trap more air than a single bulky layer, thereby allowing less heat to escape. Before discussing the actual layers, let s first set out a few rules that must be followed. Drink plenty of water. People have a tendency not to drink enough water in cold weather.
Proper hydration is necessary to stay warm.
Eat foods high in complex carbohydrates and increase intake of fats. Do not drink alcohol. Keep all exposed skin covered to prevent frost bite. This is especially important under windy conditions. Keep your head and neck covered.