Here's a fun way to mix it up for your dino-lover's birthday cake: different colored tiers! Bake two two-layer cakes (the smaller layer in an 8-inch round pan and the larger layer in a 9-inch round pan) and cover each in a different colored frosting. Use an icing gel pen to draw the dinosaur tracks on the side of the cake and surround the base with crushed graham crackers and candy rocks. Garnish with some fun, plastic t-rex toys and create trees out of pretzels and fondant -- or skip all that work and just raid you dino-fanatic's toy chest for a couple and make them toppers. Your two-tone masterpiece will be extinct before you know it.