This costume is lightweight and easy to get on and off, and it makes an eggs-cellent companion for the Fab '50s Waitress.
To find the right length for the egg white, measure from your child's chin to the floor and subtract 8 inches. The egg's width should be about 24 inches. On the foam, draw a free-form egg white with the marker, then cut along it with an electric knife or scissors.
Trace the bowl on the back of the foam, then cut a hole 2 inches inside this line. Paint the inside of the bowl yellow (this may take several coats). Once it's dry, insert it into the hole.

To make the strap, have your child hold the egg to her chest, then apply Velcro strips to the foam and the ribbon at the appropriate spots. Trim any excess ribbon.