Horizontal: Using a level, locate the lowest point on a wall to be tiled. At the low point, make a mark on the wall the height of one tile plus 1/8". Using a level, draw a horizontal line through the mark. Extend this horizontal line to any other walls to be tiled. If desired, a wooden batten may be tacked along the horizontal working line to assist in placing the first row of tile.

Vertical: Locate the mid-point of each wall to be tiled and mark it on the horizontal working line. Lay loose tile from the mid-point to the corner to check the width of the end tile. If the end will be less than half a tile, move the vertical reference line half a tile width either way from the mid-point.