Cover your work space with newspaper, then place a terra cotta saucer onto the newspaper facing upward.
Paint the surface of the saucer using waterproof latex paint. Cover the saucer using a solid color, or use multiple colors to create a pattern or design. Allow the paint to dry for 30 minutes.
Dip shaped craft sponges into the waterproof paint, and stamp the sponges onto the painted saucer. Apply as many stamped shapes as you prefer, then allow the paint to dry for 30 minutes.
Insert a hot glue stick into a hot glue gun, then plug the hot glue gun into a wall outlet to heat up for 10 minutes.
Squeeze a pea-sized dollop of hot glue onto the edge of the saucer, and press a flat glass marble onto the hot glue dollop. Allow the hot glue to cool for two minutes. Repeat to hot glue flat marbles around the entire edge of the saucer.