Clean your aluminum surface well. Remove and wash the piece if possible. Dry it completely after cleaning using a terry cloth or microfiber rag.
Sand your aluminum surface if you have serious scratches or scrapes. Use a only aluminum oxide sandpaper and a grit that will take out the blemishes. Then finely sand with 800- to 1200-grit sandpaper, depending on the hardness of your aluminum alloy, to soften the sandpaper scratches.
Apply a metal restorer polish with a rotary polisher or hand drill with a wool pad. Hand polish crevices and other hard to reach areas with a clean rag and polish.
Buff the polish with a buffing wheel either attached to your drill or rotary tool going in the opposite direction of the original polish, called a cutting stroke.
Clean the surface again and polish with an all-purpose polish by hand with a terry pad or hand drill and felt polisher. Work on one area at a time. Clean the surface again and replace the pads and towels.
Finish your polishing by cleaning and drying the surface again and using a finishing polish to get a mirror-like shine. Apply this polish by hand using a cloth diaper or your drill or rotary tool and fine felt pad. Clean again and buff well with a soft cloth or diaper.
Polish again with an ultra-fine polish if you want to go one step further. This is competition quality polish. Continue buffing until you can, according to the Top of the Line Polish Company, "rub the cloth diaper across the surface and it remains clean."
Mist the surface with distilled water. Dry it and buff again.