Forming this ring is easy - all you need is a ring mandrel and a rubber or nylon mallet.
Make sure your metal piece is flat, especially on the edges. Hammer it with
the rubber mallet if necessary.
Inspect your piece and choose which edge you want on the top. You may want to model it against the ring mandrel to get a better idea. You will form the ring with the top edge towards the smaller end of the mandrel.
Start with the wide edge and push it against the mandrel at the size you have selected. Then bend it slowly around the mandrel and hammer with the rubber mallet. Bend it around all the way and let the narrow end wrap over the wide end. Now hammer it in place carefully all around the mandrel. You have some leeway here if it is not the size you want you can keep resizing by moving it around. Eventually, the metal will harden from the hammering and become stiff.
See video Ring-Forming
If you want to polish the ring further after it has been formed you can use the steel wool or even some type of a polishing compound if you want more shine. This is a rustic ring, it doesn’t require much final polishing.
Now it is ready to wear! If the ring tarnishes you can use household ingredients (lemon juice, baking soda, etc.) or steel wool to remove some light tarnish.
If you don’t have silver wire but happen to have copper solder wire around you can use that as a replacement. It will produce similar results and/or you can even leave it partly unmelted and produce interesting bumps onto the copper. The color of copper solder wire will end up looking very similar to silver.