I was thinking today about my nail polish collection, and how people like to put a little bit of polish on top of the caps to make it easier to find the color. The only issue I have with seeing to color are with my Julep bottles. Julep came out with a batch of Swatch Me stickers. I know they came with a Maven box, I didn't not get that one, and I haven't seen them online yet.
I decided to take the cheaper route, and grab my hole reinforcements. I cut them into four parts, and placed them on the caps. I them popped the cap off (super easy to do), and put the polish on the sticker.
Quick, cheap, and super simple. I don't know how this will work for other brands, I know the Butter London caps pop off (there's no other way to use them without popping them off), but I don't know of any others.