Wool is moisture-wicking and odor-resistant, while synthetic fabrics are more durable and less expensive.
Match the temp to the trek
Lightweight layers are best for moderate to cool temperatures. Midweight layers are best for cold temperatures. Heavyweight layers are best for below-freezing temperatures.
Find your fit
To be able to wick sweat efficiently, your next-to-skin layer needs to actually be next to your skin. A comfortably snug fit everywhere is your goal.
A water-resistant jacket can handle light rain for a brief time and is more breathable
Windproof vs. wind-resistant
Any waterproof jacket is also windproof to shield you in stormy weather
A wind-resistant jacket will offer much lighter protection
Hard shell vs. soft shell
Like a waterproof and windproof rain jacket, a hard shell will offer the most protection, but less breathability than a soft shell.
Do you need insulation? For very cold rainy weather, consider an insulated shell, which will have down or synthetic fill for warmth while being waterproof and windproof.
