Vacuum the tiles with the brush attachment of the vacuum cleaner to remove all dust and debris.
Apply painter’s tape around the perimeter of the tiles to keep cleaning and glazing products from spreading to these areas.
Fill a bucket with hot water, and add a tile-cleaning product to make a sudsy cleaning solution (consult the product label for mixing instructions). Dip a scrub brush into the cleaning solution, and use it to scrub the tiles thoroughly. Rinse the tiles with a clean cloth saturated with plain water. Allow the tiles to dry completely before you continue.
Load a paintbrush with terra-cotta glaze, and apply the glaze onto the tiles in a thin, even layer. Allow the glaze to sit on the surface of the tiles for approximately 30 minutes. Wipe the tile surface with a clean cloth after the time elapses to remove excess glaze.
Apply a second coat of glaze immediately after you remove the excess glaze. Allow the second coat to dry for 30 minutes again, then wipe off the excess with a clean cloth.
Allow the glaze to cure on the terra-cotta tiles for 72 hours. Resume light foot traffic after eight hours, but wait to reposition furniture on the tiles until after the curing period elapses.