JUst keep in mind, its not the buffer thats the most important. buy a cheap one if occasional use. However I have followed these level of importance when choosing the materials, they are the most important
1. Choose a foam pad if you are new, choose a quality pad. Its not the buffers fault, or the compound in most cases. The pad does the work
A. I got great results from the Blue foam finishing pad from 3M
B. I cut using a black wool presta pad
2. Compound. I have used Presta, 3M, Evercoat Body Magic, Mirka Polar Star, Cumberland, Transtar products. All pretty much yield the same results.
A. I cut using Evercoat Triple Cut Compound
B. I finish using Presta Chroma Polish
C. Wax using Meguiars 26 (by hand) No switl marks at all even on black
3. Backing pad, I use a presta. It is flexible. Use a flexible backing pad, if not you run a higher risk of burn through.
Keep the pads clean, dont use water to clean a wool pad. Use a cleaning tool regularly when cutting, The cutting process creates alot of trash that contaminates the finish and can make swirls. Foam pads can instantly cleaned with water, dried, spun, and buff again. As mentioned before I get rid of the trash in the paint with the wool cutting, constantly clean it, then polish with the blue.
You will get good with practice. Here is my Black GN that I just finished painting. Notice in one pic the grain in the paint before finishing, then look at the flash in the second pic after I was done buffing.