For Brenda: Well, you're a hot dog bun, so either buy a giant, foam hot dog bun costume, or wear a nude body suit and paint a long black stripe down the middle.
For Frank: Well, you're a hot dog, so either buy a giant, foam hot dog costume, or wear a brown body suit and paint a yellow or red squiggle down it to make sure people know you're a hot dog. Add white gloves.