craftgrrl | Text only because my camera's not working

Right, so, I've got some plain, cheap, brown air dry clay to use up, and I figured I can make small bead type things and bits of jewelry supplies with it. However, the brown is pretty ugly and I'd like to be able to paint over it and then doodle or write little designs (symbols, people's initials, etc) on the clay once it's dried, maybe even with a plain old Sharpie marker. My question is what kind of paint/ other material would I use? I'm afraid of any colour or ink getting rubbed off because the clay's pretty dusty and smudgy. Is there some kind of sealant I could put on after that would keep that from happening?

Thanks.