Most people want to sand and buff there new paint job right away. Yes the paint is softer, but take a minute and sit back and think about it for a second. You spent all that time in producing a beautiful paint job and then you just cant wait to grab some 1500 and knock it down flat. To me you are just setting your self up for failure. I have learned from experience to let the paint cure for a few weeks or even a month or so. I just finished buffing out a caddy that I painted over a month and a half ago. The paint was fully cured which means two things. One I started off with 1000 grit instead of 1500 and just worked my way up to 1500. Two I don't have to worry so much about burning the edges because they are not as soft as that week old paint job.
I use the 3M perfect it 3000 heavy cut with a foam compounding pad. I start off with a nice size X of compound on an area about two feet by two feet. I've seen people who will just continue to buff that sucker dry. In my opinion that's wrong. I keep it semi wet. When I see the compound start to slowly dry as I'm buffing I stop and get a little squirt bottle with some soapy water and mist a little water on top of it and then continue back buffing. I never let the compound dry fully. I want some swril marks in it still because then I know that its still wet and will help prevent burn thru. When I feel comfortable with the progress of the shin that I'm kinda seeing, I go ahead and wipe it dry with that once again white T-shirt. Now you will be able to see how the shine is developing.
Now that I'm happy with the gloss, I change pads and go for the machine glaze/polish. I put about 4 to 5 little drops on a 2x2 area and start buffing. Once again I want it to maintain a little wet, not as wet as the compounding phase but close. When I see it starting to dry, I mist a little soapy water on it and continue until I get that deep luster shine that I'm after. Sadly I actually use more water than the polish, but who cares because its the final shine that I'm after.