I am trying to mix royal blue and a little black together to get the dark blue for spots on a blues clues cake. I am not having any luck. Does anyone have any suggestions on what colors to use? I am still learning as I go! Thanks

what are you mixing it for is it fondant or icing?

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

Here's a color chart. It may help.

I am using buttercream and wilton jel colors. I tried the sky blue and violet, but I am just using a toothpick and I seem to be getting more violet! Is there an easy way to measure it out?