If you do a quick search, there is plenty of discussions on this procedure.
If you don't want all the trouble of taking things apart, you can paint the calipers while they are still on. The back side is not really visible anyway. You can use engine paint. There is the 500 degrees version and a 1200 degrees version. The colors usually come in flat or gloss. You can also spray layers of clear on top. There is also a system (G2) where it is a brush on. This is a little more expensive but you don't get overspray.
It really depends how far you want to take it. You can paint, put caliper stickers on, then clear it. You can even machine down the front to smooth it out for a different look.
To start you off, look here for some info:
There is a section for paining the calipers. It is BananaGS's site and it has a ton of other useful info.