Target was getting rid of a bunch of place mats for 99 cents each about 3 or 4 days ago so I picked up 2 (one for my feet and one for hubby though I haven't made his yet.)
Anyway I thought I would show off what I did with a kinda picture tutorial (original is here).
I started off making a foot form for the sock blocker and testing it out by putting one of my socks over it. It is was not fitting I trimmed and if it was loose I added cardboard with tape.
I traced the cardboard with a dry erase marker. (dry erase makers will erase off of most plastics and glass.) This way I got a mark but could remove it easily and not have it mar the finished product.
I ended up making the cardboard pattern to long in the leg so I just trimmed it off. Looks good if I say so myself.