Just throwing this out there. Does anyone know where I can find more info on making my own keshi-style rubber figures, ie M.U.S.C.L.E.?

I've seen a few keshi-style motu figures out there as well like fisto, skeletor and beast man. I've been able to find plenty of shops to buy figures, but have had no luck on finding any how-to's.

Any help would be appreciated! Thanks!