Beginning at the center mark, set the tiles firmly in place in a straight row, making sure the spacing lugs are pressed tightly together. Do not set the corner pieces in place yet unless no cutting is required.
After the first row is complete, begin on the second row (Image 1). Repeat this process until the tiles are at the desired height. Periodically check your work to make sure the rows are level (Image 2).
Cut the corner tiles to size, using a tile cutter (Image 3) for straight cuts or a tile saw for irregular cuts (Image 4).
Set the corner pieces in place with the cut edges facing the corners. This will make them harder to detect when the project is finished.
Place mastic directly on the backs of the bull-nose tiles (Image 5). This process, known as back buttering, allows you to put the appropriate amount of mastic on the tile without worrying about putting too much on the wall.
Allow the mastic to dry, then mix a batch of grout according to the manufacturer's instructions. Grout is typically mixed to the consistency of peanut butter.