Originally Posted by
rm -rf
Below about 40F, I have an inexpensive "neck gaiter". It's just a tube made of fleece. I can push it down around my neck, or pull it over my mouth and nose on downhills.
You can also fold it in half (or quarters) and cover your ears and forehead. I have a thin wool one, it's warm when I fold it, but stuffs into a pocket.
Wool just about everything, wind breaker, and an insulation layer when it's cold enough to need one. When it's really frigid I'll bring a down vest in a stuff sack, carry it in a bottle cage, and throw it on over the wind breaker. But it's got to be below freezing for that.