1. Use the right paint - any of the Caliper paints or HiHeat paints will do
2. Cleaning thoroughly is your best defence against paint peeling later - use Wax & Grease Remover or BrakeKleen, and clean cloths
3. If you have access to a wire wheel, use it to clean up rough spots
4. Disassemble the calipers as much as possible, tape off the pistons area, the bleed nipple (or remove it)
5. In between light coats, use a heat gun to keep the caliper warm (but not over hot) - this will cause the paint to cure faster
6. Three coats is all that is needed if coverage is good - the more expensive paints have better pigmentation and better coverage
7. Allow to cure overnight
8. Assemble and enjoy

Peter