How to Put Tiles on Walls With Thin Set Mortar

Draw a horizontal line along the bottom of the wall, using a level and pencil. Set the line up from the floor by the size of a tile plus 1/4 inch. (Example: If the tile is four inches high, the line should be 4-1/4 inches up.)

Mark a vertical line through the middle of the wall, from top to bottom.

Spread thin set mortar over the base of the wall, under the horizontal line, from end to end, using the notched tiling trowel.

Press a wall tile into the mortar, with the top of the tile lined up with the horizontal line, and sitting to one side of the vertical line. Hang more tiles next to it, building out to the edges. Put spacers between the tiles as you go.

Cut the tiles at the ends of the course using a tile cutter.

Apply more mortar above the bottom row of tiles. Press the next course in place above it, again starting at the center and working toward the sides. Repeat the process, building up the wall row by row until it's covered.

Let the mortar set for 12 hours.

Grout the tiles, pressing grout into the spaces at a 45 degree angle with a grout float. Wipe off the excess grout with a damp sponge.