These will keep you warm, even when wet. On a canoe trip your pants are guaranteed to be a little wet at least some of the time. Similarly, cotton T-shirts alone do not a wardrobe make. Bring a few along, but make sure that you have a wool or synthetic sweater as well. On longer trips it is often best to bring 2 sweaters, one lightweight and one heavyweight.
Feet are the most difficult item to keep warm .
For people who bring nothing but cotton socks warm feet soon become a distant memory. At least 3 pairs of wool socks are mandatory on most trips. Nylon running shoes dry very quickly if they don't have a lot of padding or leather. Some people like to bring a set of rubber boots which work great if you have woolen or synthetic socks on underneath. Both of these items are made of a thin neoprene and will retain incoming water against your skin, allowing it to warm up.