Body heat and the winter cold keep your clothes dry
Keeping your clothes dry is a never-ending chore during a winter trek because you will get wet - whether from melting snow or your own sweat. If you have the possibility to take a break in a warm space at some point during your trek, you should take advantage of this, but it is still possible to dry your clothes even in the bitter cold.
Your own body heat can dry out damp clothing. This is practical to do when you are moving around, for example at your base camp, taking care of simpler chores. Socks, gloves, hats and insoles can dry while you are trekking by hanging them inside your shell garments, at the armpit or along the thigh. Your body heat and the ventilation of the shell garment will push out the moisture. Remember, though, not to hang them directly against your skin, since this will lower your body temperature.
It is also possible to freeze-dry wet clothing, for example if you have washed them (which can be necessary on longer treks since dirt can lead to blisters and other discomforts). Rinse your clothing, squeeze out the water and hang the garments in the tent overnight. When the water has frozen, you can rub the fabric and shake out the ice crystals. Then hang the garment under your shell, as described above, to get rid of residual moisture while on the move. In sunny weather with a light wind, you can use the wind sack to dry your clothes. Hang your wet clothes inside the sack; it will function like a drying cabinet or green house and the rays of the sun and the wind will force out the moisture.
Watch out for hot heat sources
A wood-burning stove or an open fire naturally offers an excellent opportunity to dry your clothes but be careful. Leather can shrink and glue, for example in the sole of your shoes, can melt. Some synthetic materials, such as polypropylene, show signs of deformity at relatively low temperatures.