When my daughter broker her leg, the one thing that made everything okay was that she knew she'd be able to draw all over her cast. She did a pretty good job covering the surface of her white cast with Sharpie doodles. But when the doctor decided to over-wrap my daughter's cast, my daughter chose purple. Not a bad choice considering her glasses are purple, but when she realized her markers wouldn't show up on the new darker surface of her leg, I thought we'd be in trouble.
Silver Sharpies to the rescue!
The markers show up wonderfully on the surface of her cast and my daughter can resume personalizing her leg. The silver version of these markers have the exact same tip the other colors have which is a big plus for me since normal silver paint markers can be a little bit awkward. Yeah, silver Sharpies!