Continue with different colors, and then let the paint dry. Seal the paint with two or three coats of polyurethane. If you like, finish off the design by attaching a few glass beads to the pattern with industrial-strength adhesive made specifically for glass . There are special fabric paints that won't make fabric stiff. Buy them at a craft store.
Metal comes in so many thicknesses.
If you have a very thin metal, you can use just a stylus. But if you have a thicker metal, you may want to use a heat gun and embossing powder. It doesn't really press into the metal, but it gives the illusion of embossing. But you can buy your own foam sheets, design your own pattern and then cut it with ordinary sewing scissors.