Spread a thin layer of silicone sealer adhesive over the surface of the trivet with a small trowel.
Press 1-inch square ceramic tiles onto the sealer-covered surface spaced 1/8-inch apart. Allow the glue to dry for four to six hours.
Spread an even layer of fine grout over the entire surface of the trivet with the trowel and push the grout into the spaces between the tiles. Scrape off any excess grout with the trowel.
Wipe off the surface of the mosaic trivet with a damp sponge to remove the grout from the top of each tile. Allow the grout to dry for six to eight hours.
Cover the mosaic pot trivet with a thin layer of masonry sealant applied with a paintbrush. Allow the sealant to dry for four to six hours before using your colorful, new trivet.