Mike Wazowski is the one-eyed monster from the 2001 Disney movie "Monsters, Inc." A costume can be made to resemble him using an exercise ball and a few other items.
Step 1: Make a paper mache form using a large exercise ball.
Using glue and newspaper, cover the ball and let it dry.
Step 2: Create an eye from a Styrofoam ball.
Cut the Styrofoam in half, and glue it in the center of the ball.
Step 3: Cover the form in paper mache and paint it.
Paper mache the whole ball, including the eye. After it dries, paint it green and add the eye details.
Step 4: Cut the holes.
Add holes for the head, arms and body. Pair the costume with a lime green shirt and leggings.