I kayak fish in waters that are pretty cold, sometimes the air is pretty cold as well, so I've got the
kayak fishing wardrobe pretty well figured out. How cold? Went out a few days ago, water and air were both in the lower to mid forties.
If it's really cold, I wear waders with polarfleece long johns and wool or waterproof socks. Of course you should always wear a wader belt, looks like a lot of wader manufacturers are starting to provide one with the waders. I have gone into forty degree, fast moving river water with waders with a belt; pretty cold but not much water got in the waders.
Dry suits are OK for extreme cold, otherwise, without being
in the water(like a surfer or diver), they are too hot. Wetsuits, without a layer of water between your skin and the rubber, can be very cold. Most of the time I wear
waterproof pants with
polarfleece underneath, waterproof socks and
neoprene wading booties with a felt sole.
On top, usually a fleece pullover and GoreTex shell(rains a little bit up here).