Polishing Aluminium Parts

Hey guys,

I was wondering if someone wants to share a little how-to-guide on who to polish scratched and faded Aluminium parts like the engine/transmission cases or the wheelhubs. I saw some guys making those parts look like they just came out of the box, but since I'm new to that topic, I'm not sure how to achieve that (e.g. ideal sandpaper grit, polishing products etc.). Interested to hear what worked for y'all.

Thanks for the help!