I do home health and have someone with very large lower extremeties due to permanent swelling so my project is a tube sock/slipper approach with ribbing... The pattern is k2p1 ribbing that after the ankle part is funneled down to k1p1. I am using worsted weight yarn for my trial sample and am going to spray "Dip it" tool coating lightly on the bottom to form a non-skid sole. Ribbing is probably the best for size retention...has anyone thought of adding in wooly nylon for reinforcing and stretchiness??? I have used this in the past for sewing swimwear with my serger...very stretchy without constriction. It also comes in a variety of colors. Tube socks are a little more forgiving.