This year my son decided he wanted to be Plankton from Spongebob. I used all felt. Ah, wonderful felt…cheap, easy to use and great results. I created a sheath shape by placing two pieces of green felt together and sewing the space between the armpit and the thigh. You don’t want to go lower, because then the child can’t walk or sit. I also sewed the shoulders together after fitting it on him directly so he would be able to take the costume off over his head without any issue. (no need to sew on closures this way!) Using a picture of Plankton as a guide, I cut out the facial features to fit my son’s frame. The hardest part was the teeth. I ended up being able to get the right shape when I put the white felt over the already cut black felt and cut a singular piece following the upper lip line (lower lip for the bottom teeth). I then came back in and cut out individual teeth and shaping the bottom tooth line appropriately. I used a great easy iron on product to adhere the felt shapes to the solid green background. Pellon 805 Wonder Under- http://pellonideas.com/products/1001-805-wonder-under.aspx This stuff was awesome. No sewing or glue, just ironing and the pieces looked really nice in the end.
Plankton was a big hit!