- 1). Install the main section of regular tile with thinset mortar, with the correct spacing between the tiles. Stop the tiled area where you want the trim tile to go. Let the regular tile set for a day. Don't grout the tile.
- 2). Measure along the edge of the tiled area, using a tape measure. Put a pencil mark at the middle of the measurement.
- 3). Spread thinset mortar over the back of a trim tile, using a putty knife. Cover the back completely, to a depth of about 1/8 inch.
- 4). Press the trim tile onto the wall, next to the regular tile, with one side of the trim tile lined up with the pencil mark and the finished side of the tile facing outward from the tiled area. Put spacers between the trim tile and the regular tile.
- 5). Repeat the process for the other trim tiles along the edge of the tiled area, mortaring each of them into place from the middle of the border and working out toward the edges. Put spacers between the trim tiles, and next to the regular tiles. Cut the trim tiles at the edges of the span as needed, using a tile cutter. Let the tiles set overnight.
- 6). Pull out the spacers. Apply grout to the whole tiled area, both trim and regular tiles, using a grout float. Press the grout into the spaces and squeeze it off the surface. Wipe away the excess grout with a damp sponge.
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