Your not going to use a primer?
I did 2 coats of primer when I did mine before applying the base coat.
The only sanding I did was before applying the primer then cleaning the rim, then sanding between the coats of primer and between the primer and base coat.
As far as applying the base coat and top coat, I did for each: 1 dust coat(light coat) and 2 proper coats at least.
Don't get too enthusiastic with the paint as its easy to get runs.
Masking the rim with tape is a good idea too. Or another way to do it is to smear vaseline on the area's you don't want the paint, and simply wash it off after the paint is dry. Masking is probably easier though.
When putting your wheels back on, wrap your wheel nut spanner head with electrical tape, it helps protect the paint on your rims.