Decorate side of cake. Place cake on inverted 6 in. round pan. Use yellow icing pouch with coupler and tip 102 to pipe scallops around the cake on the 1 in. markings with the narrow end of the tip down. Use white icing pouch with coupler and tip 102 to pipe scallops slightly overlapping yellow ones. Repeat until you have six scallops.
Use white and yellow icing pouches with tip 102 to fill in the gaps at the bottom of the cake, creating a three-row scallop.
Use yellow icing pouch with tip 102 to pipe scallops around the cake on the 1 1/2 in. markings with the narrow end of the tip down. Use white icing pouch with tip 102 to pipe scallops slightly overlapping yellow ones. Repeat until you have six scallops.
Repeat above steps to top of cake. Place cake on cake platter.