When I wet-sanded my car, I went through a lot of trial and error. It had VERY bad orange peel:
I compared Meg's unigrit paper to regular 3M paper, and I really like the Meg's much much better. The 3M stuff is just fine for 1200 and 1500, but when you go to finish it off with 2000, 2500, and 3000 use Unigrit. If you get all the way up to 2500+, you won't need to bother with wool pads or heavy compounds. While it's prefered to buff out wetsanding marks with a rotary, I suppose a PC with some very aggressive stuff may work.
Anyways, as you are sanding, make sure you spray some QD and wipe the area dry with an MF. You should be able to notice an amount of smooth and dull paint... basically the deeper valleys and the higher ridges. The ridges are being sanded off, so that's why they are dull while the valleys remain shiny, as the sandpaper hasn't cut them yet.
As the ridges and valleys get smaller and smaller, start moving up the grades of grit. You should be at around 2500-3000 by the time it's flat. Every once in a while, I would buff a little "window" with some sort of compound by hand, just to see my progress.
You'll know when to start buffing once the paint is totally flat, and no more of the valleys/ridges appear.
I used a rotary with meg's burgandy pad and some 3m Medium Cut stuff. Then, I went down to meg's fine cut with the same burgandy cutting pad, and then swirl free polish with the meg's yellow polishing pad. Many different products could be used, but I went with these since they were readily available and pretty easy to use, with the exception of fine cut cleaner. That stuff is such a pain to wipe off.
