Clean the tiles thoroughly with a tile cleaner to remove any buildup or residue from the tile surface and grout before adding decorative decals or paint.
Apply transfers to the tile if you don’t want to change the color entirely. There are a variety of tile decal designs or colors that allow you to mimic the look of accent tiles without the cost or demolition. Choose geometric, floral or themed decals and peel and stick them as directed by the manufacture onto the tiles of your choice.
Paint the tiles if you have an outdated color. Rough up the surface of the tiles to prepare them for paint by sanding them lightly with a 220-grit sandpaper.
Wipe down the tiles with a dry rag, then cover the tile with a primer designed for glossy surfaces to give the new paint something to stick to. Apply oil-based, high- or semi-gloss paint to the tile with a roller or brush, depending on your preference. Go slow to prevent paint or roller marks on the tile.
Allow the tile to dry slightly, then add one to two more coats to provide uniform coverage. Allow the tile to dry at least 72 hours, then seal the tiles with a water-based urethane clear coat. Allow the tiles to dry 24 to 48 hours to fully cure before running the shower and creating humidity in the bathroom.