I'm trying to make maroon icing and i am not
sure what colors I need to use. It's for a graduation cake.
Any help would be great. Thanks

Maybe this chart will help you out...

http://www.cakecentral.com/modules.php?name=gallery&file=displayimage&pid=858073

CK makes this color; it's called "maroon." I've used it before. It has a plum/purple hue as opposed to the burgundy hue I was looking for. But, it might work for you.