Ceramic trim tiles are typically bull-nosed versions of regular tiles and are used to finish the ends of ceramic surfaces at the corners where they meet other surfaces. Ceramic trim can, however, be used to finish the edges of other surfaces, including laminate countertops, concrete basins and plastic or fiberglass shower stalls. Install ceramic trim around your shower stall to protect the seam from water and to add a decorative border.
Cut out any existing caulk from the seam between the shower stall and the wall, using a razor blade.
Clean the area thoroughly with degreasing cleaner, using a scrub brush. Dry the area.
Make a few marks on the wall above the stall, measuring where the top of the trim tiles will sit. Connect the marks with a yard stick and make a solid line.
Sand painted drywall in the space above the stall walls where the tiles will cover, using 80-grit sandpaper. Sanding is important mostly if there is gloss paint on the wall. Wipe away any dust left from sanding with a moist towel.
Secure the tiles to the wall with tile adhesive. Apply an even coat of tile adhesive to the wall and to backs of the tiles, using a notched trowel. Press the tiles in place, leaving 1/16 inch between each tile. Leave the tile adhesive to dry overnight.
Push grout into the gaps between the tiles with a rubber float or squeegee. Leave the grout to set for about five minutes, then use a damp sponge to wipe residual grout from the surfaces of the tiles. Leave the grout to cure for three to four days.
Extrude a bead of siliconized acrylic caulk along the seam where the top edge of the tile meets the wall and the seam where the bottom edge of the tile meets the stall. Smooth the caulk down with a forefinger.
Leave the grout to cure for another three to four days, then paint the grout with grout sealer with a small, round paintbrush