Clothing is a form of shelter. Clothing is needed for protection from the elements and protection for the body.

Wearing two or more layers of clothing is the most effective method for keeping warm. Layers of clothing trap what is known as "dead air" between them. Dead air is air that is not moving, and as such, able to remain heated by the body. Using multiple layers as opposed to one heavy garment traps more of this dead air and keeps one warmer. Another benefit of layers is the ability to take clothes off or put clothes on according to changes in temperature.

These guidelines are for optimum outdoor warmth and water resistance.

The first layer of clothing, the one touching the skin, is very important and needs to have certain properties. One of the properties is known as "wicking". Wicking is the ability of a material to pull moisture away from the body just as a candle wick pulls melted wax to the flame as it burns. A cloth with wicking properties will keep one dryer, warmer, and feeling more comfortable. Common materials with good wicking capability are wool and various synthetics such as polyester.

The second layer of clothing needs to keep you warm. Wool is a very good choice for this as it is quite warm and it retains warmth even when wet. Cotton is another warm material but cotton completely loses its warmth when wet. There are also a wide variety of synthetic materials that would work well and retain their warmth when wet.

The outer layer of clothing, the third layer, works best with water resistant qualities. Synthetic materials such as nylon are good at repelling water and keeping the other layers dry. The main drawback of wearing a plastic outer layer is they are noisy during movement.

Having needles, thread, and patching materials handy is vital to keeping clothing in good shape. Also, for optimum use, it is best to keep clothing somewhat clean.

The most important areas to keep warm are the hands, feet, and especially the head. The hands and feet are the parts of the body that get cold the quickest, but most warmth from the body is lost from the head. A good hat is a very important aspect of keeping warm.

Having a decent pair of boots is also very important. Boots can be fairly expensive but they are worth it. Be sure to try and get a pair that is waterproof and durable.

Gloves are another critical item for warmth.

By wearing darker clothing, you won't need to wash your clothes as much. Lighter colored clothing shows stains and dirt more easily.

One drawback of wearing dark clothes is that they attract more radiation. Victims of the Hiroshima bombing who were wearing lighter colors were far less burned than those wearing darker colors. Yet, darker colors keep you warmer by attracting more energy from the sun.

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