I made this costume (and Ranma's dress) for a cosplay team photo shoot for Ger Tysk's upcoming book "Breaking All the Rules: Cosplay and the Art of Self-Expression". My best friends and I picked this set of costumes to showcase our love of old school anime and because we've had Ranma 1/2 on our "to do" list for years.
I ended up taking some artistic license with parts of the dress so that I would be able to wear a bra and not be flashing everyone around me. The dress is made out of "Sunshine" yellow Casa satin and is fully lined. I used a pattern to get the basic shape of the top of the dress, but I ignored the darts for the top because Shampoo's dress isn't fitted or structured. I drafted the patterns for the skirt, waistband, and for the bow. The bow is made out of a combination of 4 jumbo sheets of craft foam, 12 gauge wire, batting, and glue, all of which is then covered in the same fabric as the rest of the dress. The bow connects to the waist band with 4 large snaps and can be re-shaped as needed thanks to the wire. The shoes are ballet flats that I painted with some green fabric paint and the green "ties" are satin ribbon.
For the wig, I teased and hair sprayed the bangs to get them as voluminous as possible. The forelocks of hair are secured with clear elastics, so I can easily change out the hair accessories if I want to do a different outfit. The hair buns are made from one 4" styrofoam ball cut in half, covered in purple felt, and then covered in wig fiber. The buns are then hot glued into place on the wig.