I start out a little more agressively than most folks. I've found that if you have swirls and marring, it tends to be a waste of time to start in any other way. You aren't going to hurt anything with a pc and the products and procedure I recommend below.
Clay the car first if it needs it . Then here you go:
1. Meguiar’s #83 DACP, cutting pad, pc at 5.5, medium pressure, work the product until it is almost dry.
2. Repeat if necessary. (Or repeat using a polishing pad.)
3. Meguiar’s #82 Swirl Free Polish, polishing pad , pc at 5, medium pressure, work until almost dry, but not as dry as DACP.
4. NXT, polishing pad or finishing pad, pc at 3, light pressure, work only to insure full covering.
5. Repeat with NXT after 24 hours.
Remove all products with a microfiber polishing cloth. It makes the job a whole lot easier. I've messed with other products, but I always seem to go back to Mequiar's. NXT looks darned good on black by itself or if you choose you can top it with a carnauba -- S100 or Meguiar's #16.
I know black. See my signature. Been "in black" since 1977.
Good luck!
Tom :cool