Decorate cake. Prepare four decorating bags with tip 2A. Fill separately with teal, green, yellow and orange icing.
Using cake marker, divide cake into four sections – placing pins at 1 ½ in., 3 in. and 4 in. marks. Lightly mark cake.
Place cake on turntable. Starting at bottom of cake, fill bottom section with teal icing. Repeat, filling next section with green, then yellow, then orange. Fill top of cake with remaining orange icing.
Using icing smoother carefully smooth sides of cake. Using spatula, smooth top.
Insert candles, if desired.