I made this Homemade Rainbow Brite Halloween Costume out of an old bridesmaid dress that I found at a thrift store for $10. I cut off the bottom and used the excess to make the sleeves and wristbands. I used rainbow socks for the leggings and arm warmers and sequin suspenders that I found at Hot Topic.
I couldn’t find a rainbow belt, so I bought some rainbow belt fabric from the craft store with some belt rings. I hand sewed all the sequins for the red star on the center and attached it. I also hand stitched the yellow stars on the wrist bands and used hooks to hold them on my wrists. I used some yellow fabric to make a choker, and stitched sequin circles on it.
The wig was the hardest part. I bought a long $5 one from Wal Mart and cut it off, then sewed the extra around the edge. Using hair spray, I folded the hair back into a ponytail, leaving some out around the front for the bangs, and it worked pretty well. The bottom white edge I made using some white satin that I sewed into a tube, stuffed, then hand stitched around the bottom of the dress.
Finally, I found the red shoes on clearance for $5. The whole costume cost around $35 and took about a week.