Find the coin you want to use. Quarters are probably the easiest to do.
Find someway to make sure you get the hole perfectly centered. If it's off center, it makes for a difficult ring.
Make your hole.
Heat it up so it's easy to work with.
It should look like this when it's cool.
Begin the hammering.
Hammering is the hardest and most tedious part of the process, it takes quite a few rings to get this technique just right.
After awhile, you should end up with something like this.
Continue to apply heat and hammer until you get a solid ring shape. The top edge in this one has already begun to be polished.
Second hardest part of the process, polishing it without losing all the detail.
The finished product.