I use them a lot to color my acrylic rhinestones, which works beautifully! The pack this comes in has a space at the bottom that I put a sample of each color. I just used glue dots to attach them after I colored them.
An easy way to color them is to put a strip of adhesive down, then put the stones on there & color them, they dry almost immediately & if you pick them up right there is already adhesive on them!
I learned these awesome tips from Tammy at http://www.cricutcritters.com/ she has the best retreats & ideas! I always learn a ton of stuff from her! Thanks Tammy. :)