You can put it onto the drywall. You want it smooth and to not have a glaze, so you may have to sand it. If its been painted with a topcoat, you may want to paint it again with a primer.

Use motor specifically designed for glass tiles, not ceramic tiles.

You can put it onto the drywall. You want it smooth and to not have a glaze, so you may have to sand it. If its been painted with a topcoat, you may want to paint it again with a primer.

Use mortor that is specifically designed for glass tiles, not ceramic tiles.