how do I determine how much fondant I need to color in order to have enough of the exact same color....i need to make 3 circles....12", 14" and 16" diameter and cover 2 each fake cakes 2" high by 6" in diameter. i need to do a color that i have to make myself..ie match a bridesmaids dress. if i don't make enough i may not be able to match the second batch exactly but i don't want to have so much left over that i may never use., help!!!!

Here's a guideline by Satin Ice, hopefully it will help:
http://www.rolledfondant.com/product.htm

Here's one from global sugar art and looking at it I'm thinking that perhaps the Satin Ice one may be for 2" high cakes. I'd call Satin Ice just to confirm this though.

http://www.globalsugarart.com/?id=24

HTH!

I'm a freak about stuff like this. When I watch someone on tv apply fondant to a cake it's like omg they have enough left over to cover the next size larger cake omg why did they do that <faint>

If you get already colored fondant oh well--go for it. but if I'm mixing colors....

But something I do is make a small blob of concentrated color say like one pound of fondant that's way too dark but when it's added to white it's the right shade-- then I'll add it to my big blob of white and reserve some of the original color blob to use as seed if I screw something up.

You gotta kinda do some measuring but that's an idea for you. It helps me feel more secure. I mean by the time you knead that giant monster out and get it applied and then you discover you need a little bit more....--aighhh--one of Dantes' inferno levels huh

So if I have a little in reserve I'm happier