While you are painting it have it closed into the shape it will be when you wear. Then after it dries don't open it any wider than necessary to put it on. You'll probably get some slight cracks that would show on close inspection but nothing very visible.[/QUOTE
Before you paint it, fasten it closed and slip it around a baseball bat, or something similar in circumference. It will not crack because the MB was in the flexed position when you paint it.