Use your child's favorite colors to create party decor for the area and party table.
Choose 2-3 colors and blow up a sea of balloons, twist streamers from the ceiling, and set up your table with solid color party ware.
Throw star confetti across the table and tie bright tulle ribbon around the seats to make it fancy.
Inside the party area, create a runway for the kids to show off their designs during the party.
Finally, create a "working" space so that the kids can have plenty of space to work. Make sure to have all of the supplies necessary for the designers to re-design their fashions. Bolts of fabric, iron on designs, glitter, fabric pen, scissors, tape, beads, buttons, etc.