I just painted my case... it was quite easy after helping 2 of my friends paint their full size cars.
I used:
3 cans of glossy black laquer paint (Plasti-Kote or Dupli-color automotive paint)
1 can of clear coat
1 can of sandable primer (use same brand as paint)
Different grades of wet sand paper like 3M imperial or Norton wet/dry
First I sanded down the paint with a sanding block and like 300 or 400 grit. DO not sand down to metal because your primer will stick much better to the factory primer/paint.
After it's smooth apply a few coats of primer and sand between until smooth.
Give a few coats of paint sanding between while moving up on grit paper to 2000 before final coat.
Apply clear coat, wet sand with 2000 and add final clear coat.
If you wet sand smooth between paints you should get a nice finish.
tips: Don't touch any bugs that may land on paint, you'll only make it worse
Spray in cross hatch pattern so as not to leave streaks (specially with metallic paints)
Start painting off the panel, then use sweeping motion so no drips
Spray in ventilated area with as little dust as possible, (sweep the area)
Be patient and let the paint dry before you sand it
clip your nails, keep your sand paper clean since one grain of sand could spell trouble
Good luck, u can see my case
here, I used glossy black which shows even the slightest error.. so I had to be careful. If I did it again, I'd probably choose a metalic or textured paint so the job wouldn't take 3 days like it took me.