Keeping good trail hygiene necessitates not just bringing sufficient clothes, but also understanding when to wash and clean them. When most hikers arrive at each night's campground, they change out of their sweaty shirts, jeans, or shorts and into something cleaner and warmer. You can also change your socks and underwear now, but some people prefer to wait until after a trail shower or before going to bed. If you don't take off your hiking clothes when you arrive at camp, you should change into new, dry clothing before retiring for the night. Wearing soiled clothing to bed is not just to sully the interior of your backpack, but it also provides an ideal environment for rashes and other skin conditions to develop overnight.
If you're going on a trip that will last more than two days, try rotating your clothing. When you arrive at a campsite, remove your soiled clothes and wash them as thoroughly as possible. So that the clothing is prepared for the next transfer, hang them to dry. If you're still hiking, you may alternatively tie these to the bottom of your pack. I usually pack two sets of clothes, one set of hiking pants, three wicking t-shirts, one mid-weight insulation layer, one heavy-weight insulation layer, a rain shell, and two pairs of socks for a normal warm-weather weekend trip (three days, two nights). I always have a clean/dry T-shirt, pair of tights, and underwear to put on with this setup.
If you're going on a trip that will last more than two days, try rotating your clothing. When you arrive at a campsite, remove your soiled clothes and wash them as thoroughly as possible. So that the clothing is prepared for the next transfer, hang them to dry. If you're still hiking, you may alternatively tie these to the bottom of your pack. I usually pack two sets of clothes, one set of hiking pants, three wicking t-shirts, one mid-weight insulation layer, one heavy-weight insulation layer, a rain shell, and two pairs of socks for a normal warm-weather weekend trip (three days, two nights). I always have a clean/dry T-shirt, pair of tights, and underwear to put on with this setup.