You can use many materials for clothing and insulation. Both man-made materials, such as tarps and tent material, and natural materials, such as skins and plant materials, are available and offer significant protection.
The selection of animal skins in a survival situation will most often be limited to what you manage to trap or hunt. However, if there is an abundance of wildlife, select the hides of larger animals with heavier coats and large fat content. Do not use the skins of infected or diseased animals if possible. Since they live in the wild, animals are carriers of pests such as ticks, lice, and fleas. Because of these pests, use water to thoroughly clean any skin obtained from any animal. If water is not available, at least shake out the skin thoroughly.
First, skin the animal. As with rawhide, lay out the skin or stretch the skin across a wooden frame and remove all fat and meat by cutting and scraping. Dry the skin completely for five days or it time constraints necessitate, dry over low heat. Use the hindquarter joint areas to make shoes, mittens, or socks. Wear the hide with the fur to the inside for its insulating factor.
Several plants are sources of insulation from cold. Cattail is a marshland plant found along lakes, ponds, and the backwaters of rivers. The fuzz on the tops of the stalks forms dead air spaces and makes a good down-like insulation when placed between two pieces of material. Milkweed has pollen-like seeds that act as good insulation. The husk fibers from coconuts are very good for weaving ropes and, when dried, make excellent tinder and insulation.