Buffing and polishing after a new paint job?

An Orbital buffer or dual action polisher will beat any kind of hand job that you can do. As for weather or not it will make a difference, I'm not sure. You might want to use a claybar a couple days after you're finished painting the car to remove any excess paint spray. You can then wash the car down with a good car wash and follow this up with some sort of a rubbing compound like 3m Rubbing compound, Meguiars #2(this stuff is a bit harsh so becareful if you use it), or any other good rubbing/buffing compound by a good company.

If you want a mirror-like finish, you should color sand it with 1500 grit then 2000 grit paper. After wet sanding it, use a high-quality, variable speed 7" buffer with a velcro backing pad. Start with 3M machine compound and a wool pad. Switch to a foam pad and re-do with the compound. Finally, use a fine foam pad with 3M machine glaze.

You should tell your painter that you plan on color sanding, so he can make sure there is enough material on the car for you to safely sand and polish without breaking through. Also ask him how soon you can start the process. I did my car after 3 days but it was a 2-stage paint with a hardener added and 30 minutes in a heated paint booth.

Read up on color sanding; I don't have time to give you all of the finer points here. You could very easily screw up your new paint job. This process takes LOTS of time and you can't rush it or you will burn the paint. It took me over an hour per body panel for EACH buffing step. That's 3 hours for the left front fender, 3 hours for the left door, etc.

Good luck; take your time and do your homework and you will end up with a car that looks like it just had a $10K paint job.