i want to strip and then sand the rims of my c13 and then mqybe polish it how would i do tht and what do i need to do it and how do i do it
If all you plan to do is sand/polish it, there’s no need to strip it. Just sand and polish. 
The only time you need to strip it is if you intend to re-annodize it.
I’m assuming you want nothing but shiny metal on the rims? You’ll need a drill. Hook the drill up to your axle, tighten, and spin the yoyo with the drill. Take rough sandpaper, roughly(HAHA) around 150 grit, and grind. Remove the ano, don’t worry if there’s still patches left, and start working your way up in grit. Use finer and finer sandpaper. Go as high as you want, you should see the difference it makes. (Shinier and Shinier), maybe use superfine steel wool to finish it off. By now, if you take your yoyo outdoors, you’d probably be sued for blinding 10 people. Good job, you’re done!
what if i just held it and sanded really hard ???
Couple of things that probably wouldn’t go too well.
#1: Time. It takes way longer to hand do it.
#2: Uniformity. You cannot sand perfectly even, and that might cause a vibe.
#3: Grinding? I’m not sure… but if you aren’t sanding in a perfect circle… wouldn’t that… make worse grinds? This one is just an idea I had.
Obviously, the greatest danger is #2, the yoyo might vibe. Also, it’s hard to get a perfect line with hand. If you’re trying to sand only the rims, using your hand might not result in sharp lines, while spinning the yoyo will give you a better chance of that.