These are fantastic. I am totally bookmarking this tutorial to make some for my daughter. The toddler slippers we bought her are always falling off.
When you day you use elastic bands in the ankles, do you mean like hair elastics?
oops, meant to type "Say", not "Day".
Speattle I used the flat elastic, it's by dritz and called braided elastic. I bet you could use hair elastics. You'd have to cut them and then sew them together as the tutorial demonstrates. I'm not sure hair elastics are cheaper though.