I polish all of my stainless and aluminum trim. I zone out with some good 70's rock on the stereo. I have a pedestal buffing to head from Harbor Freight that has held up fine. I have several different buffing discs that I keep in a zip lock bag with the compound I use with it. You cannot use one wheel for multiple grits of polish.
There is a shop in the U.S. you can send to and they charge $37.00 per foot. His process is as follows.
Straighten and hammer out dents.
File the surface to flatten or smooth.
Sand with progressively finer grits of sand paper up to 2,000 grit, use water with paper.
Glass bead the trim to get one uniform surface.
Buff with compound until desired finish is reached.
I do not glass bead mine do not have a huge cabinet to fit into.
You have to understand the physics of the buffing wheel. You cannot present an edge to the wheel or it will grab the part and boom it is bent, gone and you probably will need some attention also, lol. I worked in a hardware supplier and we had rows of buffers. There was always someone out with a broke hand or finger.
Do not wear loose clothes or long sleeves and no gloves except tight fitting rubber gloves. Never buff toward an edge. Here are a few pics of things I am working on right now. I am doing the roof rails today off my Mach 1. You have to strip the anodize and sand and polish aluminum.
The stainless is much easier since it does not oxidize like the aluminum does. The windshield trim on a vert is stainless and mine is shiny.
Any buffing compound works and any polish never really found one that was way better. The last bit of polishing is done with paste and I use hand drill with buffing wheel.