- foam sheets (I used Elmer's foam sheets in Royal Blue)
- thin elastic
- scissors and a hole punch
- a paper template (They are all over the web, but here is the one I used.)
Second, measure the elastic to fit the child's head. (Mine were a little over 12 inches.)
Third, tie the elastic through the holes in the mask, and secure with a double knot.
That's it! Told you it was easy. :-)