1. Check for runout on a wheel balancer . If the wheel's bent it may not be able to be balanced properly and you will have wasted a lot of time and money on a wheel that's no good.
2. Sand blast it. A lot of the imperfections will be removed and it will show you exactly what you are working with. Then check the outer rim surface for gouges and curb rash and repair / refinish.
3. Treat the surface the same way you would a body panel. Most blemishes can be fixed with a slight skim of filler or autobody putty.
4. Use a high solids primer or an epoxy primer . Several coats and block out the same way you would a panel. Do the front and back of the wheel.
5. Multi coats of Argent silver.
6. If using a clear coat, get a high temperature rated product or the wheel heat from braking will yellow it out.
I'm thinking about doing my wheels soon too. I agree with using a similar process as used in auto body although you don't need to go to the full extent. A 2K epoxy primer or DTM primer would be ideal although I will probably just use a 2K primer that I already have. I have used body filler before for deep scratches or to fix road rash. There is no need to block anything . There are no flat surfaces anyway and most everything is behind the trim ring. This process will be much better than what the factory did. A 2K single stage paint would be better than a spray bomb although I will probably just use a spray can that I already have. Its just a wheel that will live a sheltered life