I will try to describe some ways of producing simple bead caps using a simple punch. The punches are sold at building material or auto parts stores. They allow to punch holes of different shapes or even get rid of work with a jigsaw.
1. Sheet of nonferrous metal, with 0.3 to 0.7 mm thickness
3. Center punch or awl
4. Drill, screwdriver or drilling machint
5. Drill bit
Mark out the sheet of metal, find the middle of the cap, prick-punch the points for the future holes with the center punch or awl.
Then drill holes of the required diameter. Punch the circles.
The edges may be uneven, but it is fixable. Collect all circles on the same axle to fix all together. In the photo, a mandrel serves as the axle. But you can use a screw of a suitable diameter with two nuts.
Clamp it in the drill, screwdriver or drilling machine and process the edges with a file,, stone or sandpaper.
Now all circles are of the same size, and they have the hole strictly in the middle. Shape the circles.
At this stage, you needn't use a jewellery tools as pictured. This can be done with any tool with a spherical end or a head of a screw on a soft material, for example, corrugated cardboard. These are the caps I made.
And use them for your items...