Don't let cold water keep you from a walk on the wet side.
Neoprene waders are fertile breeding ground for the wet stinkies, and the material can become stiff after a time. After each trip, rinse them and hang to dry in a shaded spot. After an hour or so, turn them inside out to dry completely. Every few trips, give a gentle wash with bath soap (no bleach or any harsh chemicals) and cool fresh water, followed by thorough air drying.
Follow basically the same procedure for breathable waders, with the addition of periodic treatment to maintain durable water repellancy. Simms, Orvis and other manufacturers sell water repellant applicators, as well as repair kits. Tiny pin holes in neoprene or breathable waders are easy to mend; seam leaks are another story. Shuler says the kit that came with his Simms breathable waders is "the best I've found." For neoprene--which Shuler's had lots of experience with as a fisherman, surfer and triathlete--he suggests a plain old inner tube repair kit, with an extra dollop of glue on top. For a quick fix, Loon Outdoors (www.loonoutdoors.com) offers its UV Wader Repair, which cures in minutes in direct sunlight. Over the years I've patched up a lot of neoprene with Shoe Goo, basically liquid duct tape.