Make cake. Prepare batter following recipe directions. Bake and cool two 6 in. cake layers and two 8 in. cake layers. Prepare buttercream icing following recipe directions. Prepare, fill and stack cakes on cake boards for 2-layer cakes, 4 in. high. Use spatula and icing to ice cake smooth.
Cover cakes with fondant. Use fondant roller with orange guide rings to roll out white fondant 1/8 in. thick. Cover cakes with white fondant. Prepare for stacked construction. Stack cakes.
Make ovals. Tint 12 oz. fondant gray. Use fondant roller with blue guide rings to roll out gray fondant 1/16 in. thick. Use straight edge of third smallest (1 5/8 in.) and second smallest (1 1/4 in.) oval cut-outs to cut 104 ovals each. Use pink, blue and violet food color spray to randomly spray ovals. Let dry, about 5 minutes.
Use silver food color spray to over spray colored ovals. Let dry, about 5 minutes.
Decorate cake. Use damp brush to attach larger ovals to tiers and then smaller ovals to larger ones, bending slightly to create dimension.
One of the simplest techniques for decorating with fondant is to create cut-outs. Fondant shapes can be applied to lay at on the surface of a treat or dried so that they hold their shape when used as a topper.