One word, battery operated socks. Not the 1.5 volt (D battery) but the 9 volt kind (square battery). I have not seen them in years, but I still have 3 pair. I put on the electric socks, then poypro liners, and wear my boots loose. I have hunted with my feet in frozen water and never got more than a chill. My buddy has the cheap 1.5 volt ones, he tells me they help, but dont work as well as my 9 volt ones.