I make little stretchy bands from wetsuit material, black neoprene with blue nylon coating on both sides. I use neo glue to butt glue the edges and then over stitch the seam for extra strength. Then slide it over the a ring like little garter. I swear, once you cover your ring, you become ‘fearless’ , lol.
A faster option is Outchless band aids. Strategically place the band so the little pad is located where your ring is most likely going to come into contact with your Yoyo.
Option 3 is 'cohesive sports tape… Like the Yomega tape/ which is basically something you can get at any store with Medical stuff. < you just get a roll of the narrower tape or get a roll of the 2 inch wide tape and custom cut it down to your favorite width. Since it sticks to itself and leaves no residue, you can cut 3 pieces of the tape: 1 piece about 2 inches long and two pieces about 1/2 inch long. You get the two shorter pieces and stack them and then stick them to the center of the 2 inch section. (Simulating the form of a band aid), then wrap around the ring with the ‘beefed up center’ where you most likely would/will smack the Yoyo.
Sadly amazing for me, I have smacked some pretty nice metals, more often against: watches, belt buckles, knives clipped to my front pocket and large zippers on my cold weather jackets.