I feel that I should add that the placemats I used were the thick foamy type with the plasticized front. I think the tutorial called for the thin type that are basically laminated - although I could be wrong on this. I think the foamy ones will hold up just fine, perhaps even better than the laminated ones.
Next, I cut out the feet. I added an extra bit of length to each because I wanted the tops to stick out and to be kind of decorative. I wasn't very scientific about the whole thing, my feet cutouts are not exactly the same and if I were to do it again I would add extra width to the ankle/leg instead of keeping them straight all the way up the leg. Otherwise, I think these will do just fine and are pretty cute.
The girly ones. These are slightly thicker at the cankle because I learned my lesson on the first ones. I also should add that my husband (because he's better at finishing details than I am) took some light sandpaper to the edges to smooth everything out. Now the socks just slip right on the blockers.