Next up; putting them on. For the softer/stretchy materials they are pretty much straight forward. Apply an appropriate lube to your cock (Wherever you are going to wear it) and put some on the ring. Note: for rings with vibes, you may want to hold back on the lube or use only a little, this will keep the vibe in place better.
You can put it on hard or soft, you may find soft is easier since less stretching is involved. Either way, stretch it around the cock/package and release slowly. If putting it on soft, you will need to adjust it as your cock becomes hard. That is where the lube helps a bunch.
I recommend, when suitable, to use silicone lube. It will not dry out and last much longer. But any lube you wish will work (as long as it is compatible with the material of the ring), most of the time your partners natural lube (Female partner) or the lube you are using for anal or toys will keep the ring’s lube activated. If nothing else a drop or two of water will go a long way.
To remove, you can wait until you are soft (after ejaculation) or just stretch and remove. Careful of them hairs, eh?