Diy Willy Wonka Costume . All you need is a bit of cardboard, felt and glue. Here is our willy wonka, charlie and the chocolate factory inspired costume. Pin on Tis the season from www.pinterest.com Cut the wonka out on the white vinyl. To make the hat, start by measuring the circumference of the head. Make sure the length cuts across the corrugations so that it is easy to bend.