Tint icing Tint 1/2 cup icing dark pink, 1/2 cup light pink, 1/4 cup dark blue, 1/4 cup light blue, 1/4 cup yellow and 1/4 cup black. Reserve 1-1/2 cups white (thin 1-1/4 cups with 4 teaspoons light corn syrup). Prepare disposable decorating bags, separately, with coupler and light pink, dark pink, and white icing. Prepare additional disposable decorating bags, separately, with tip 3 and black, yellow, and blue icing. Position cake on plate. Ice cake sides, background areas and eye smooth with thinned white icing.
Outline cake. Use tip 3, a cut disposable decorating bag and light pink icing to outline body. Outline mane, tail, nose and mouth with tip 3 and dark pink icing.
Decorate eye. Outline eye, lashes and pipe in pupil with tip 3 and black icing. Pipe iris with light blue icing and dot eye highlights with white icing.
Decorate balloons. Use tip 3 to pipe balloons and strings with yellow and dark blue icing.
Decorate body and head. Use tip 16 to pipe stars on body and head with light pink icing.
Decorate tail and mane. Use tip 16 to pipe stars on tail and mane with dark pink icing.
Decorate bottom border. Use tip 5 to pipe bead bottom border with white icing.