I just colored up my 2 Cute Ink August stamps, including these cute turtles. The first one is done with Tombow markers and watercolored. I didn't use good paper, so it warped, but I still like it better than the other one, which is done in Prismacolor pencils. I prefer to color in pencils, but I feel like the watercolor was perfect for the turtle.
I actually used a copic in light aqua to go over the pencil to smooth it out and that worked fine, though it's probably not great for the tip of the copic marker...but my copics are kind of my last choice for coloring for some weird reason. They're even drying out! So I'll have to refill and start using them more.
If you like cute, you gotta check out Heidi's digi stamps at 2 Cute Ink.