1. Mix 5 Tbsp. paint with 1 Tbsp. water in a bowl. Place Styrofoam ball in bowl and let soak, turning every 10 to 15 minutes. When it becomes desired shade of yellow, remove from bowl and let dry.
2. To make tail, cut cuff and sleeve off extra top (if using a kneesock, cut off at ankle), and trim end into a V shape. Stuff with Bubble Wrap or newspaper; leaving 1" unstuffed at both ends.
3. Insert wooden-spoon handle about halfway through Styrofoam ball, then remove. Pour about an inch of glue into hole. Insert pointed end of tail into hole as far as possible; wipe away excess glue. Let dry.
4. Sew or pin tail onto seat of thermal pants. Trace small, medium and large spikes (draw a triangular shape or print out template) onto yellow craft foam four times each. Mark each spike with dotted line just short of the bottom. Separate all spikes into same-size pairs and glue each pair together from tip of triangle to dotted line.
5. Starting at end of tail with smallest spike, spread tabs apart, apply glue and adhere to tail. Follow with a medium-size spike, then a large one.
6. Attach remaining spikes to ski mask (as you did with tail); start with largest spike at forehead and work toward back of head, in descending sizes.