Cut each color out onto cardboard and use that template to cut out your fondant/ modeling chocolate / whatever. Then you can piece together the logo and place it on the cake. I have a program that will let me cut vector graphics on my Cricut Cake, but you can do it by hand just as well. I used this technique to make the Krystal logo on this cake: http://cakesdecor.com/cakes/17972
Jenniffer White, Cup a Dee Cakes - http://cupadeecakes.blogspot.com