Sister Halloween Costumes: Elizabeth and Jessica Wakefield From "Sweet Valley High"
What to wear: They're twins, so either you go with identical outfits for effect or you take a page out of their book and dress differently. We recommend these getups: a tummy-baring halter and light-washed jeans for Elizabeth, and a two-piece pinstripe "suit" situation for Jessica.
How to act: If you're Elizabeth, you're friendly and down to Earth. If you're Jessica, you're clever and flirtatious.