Armed with the knowledge of outdoor fabric characteristics (natural vs. synthetic) and the strategy of layering (a layer next to the skin, insulating layers, and an outer shell layer), you are ready to assemble your outdoor clothing system.Various articles of clothing can be mixed and matched to function well over a wide spectrum of weather conditions. The exact items that are chosen vary significantly from hiker to hiker. The point is to make the system comprehensive and versatile. Following are some specific guidelines for each clothing layer.Layer Next to the Skin.

1. Long underwear: Wicking fabrics like polypropylene and polyester are best. Dark-colors absorb most heat, keeping you warmer and drying faster in sunlight. Light colors are better on hot days when you wear long underwear as protection from sunburn or insects.
2. T-shirts, shorts, underwear, sports bras: These do not constitute a true "layer," but should be chosen similarly to long underwear. They should allow perspiration to pass through.
   • T-shirts in hot weather - Wicking away sweat is unnecessary, so a cotton T-shirt or tank top will suffice.
   • T-shirts in cool weather - In cooler mountain climates, when you could soak a cotton T-shirt with sweat while ascending a steep hill, and then get a deep chill when stopping for a break, cotton won't cut it. Wear light-colored (for coolness), moderately baggy (for ventilation) synthetic fabric shirts.
   • Shorts - Ventilation and abrasion resistance are the key requirements. A loose-fitting pair of nylon shorts, fitted with a nylon mesh brief, is a popular choice. Cotton shorts are not commonly worn because they cause uncomfortable chafing when dampened with perspiration. Try combiing lighweight polyester long underwear topped with a pair of nylon shorts.

Insulating layers.

In cold weather, you'll need to carry several insulating layers for both your torso and legs. There are many choices. The main objective is retaining warmth when wet. Leave your cotton sweatshirts and jeans at home.

1. Upper-body: Heavy-weight long underwear, wool shirts, sweaters, or synthetic fleece jackets.
   • Long in the torso so they tuck into or pull over the waist of the pants, preventing heat from escaping.
   • Turtleneck underwear and sweaters also provide a significant warmth benefit with little extra penalty in weight.
2. Legs: Heavy-weight long underwear or wool or fleece pants.
   • Loose-fitting or stretchy for freedom of movement.
   • Made of closely woven fabric with a hard finish for resistance to wind and abrasion. Wool and wool/polyester blends work well. Fleece pants are lighter but not as abrasion- or wind-resistant as wool.<li>Look for pants with reinforced seats and knees and with long side zippers that allow you to put the pants on while wearing boots.

Shell Layer.

The ideal shell is uninsulated, windproof, completely waterproof, and completely breathable. There is no single garment that can achieve all these objectives, but there are various strategies that come as close as possible.

1. Single multifunctional shell layer - such as Gore-Tex rain pants and rain parka, or rain gear with a waterproof/breathable coating. If this single shell layer provides sufficient breathability for you, it is probably the best way to go.
2. 2-shell strategy - Carry 2 shell layers: a breathable layer of wind gear plus a nonbreathing set of rain gear. Wear the wind gear in breezy and possible lightly drizzling conditions; put on the rain gear when it rains more heavily. This strategy can be cheaper, and the wind gear allows for better ventilation in dry weather. But the nonbreathing layer will be more uncomfortable in rain, and the additional shell layer adds weight to your pack.

Breathability is typically not as critical for the legs as for the torso. If you find nonbreathing rain pants comfortable, you're better off with the cheaper, nonbreathing pants, as they tend to get easily trashed from bushwhacking through brush or glissading down snow.

Apparel: Caring for Your Apparel

Apparel: Understanding Outdoor Apparel