Before beginning to lay tile, start with a "dry layout" to get a good idea about accurate placement of the tiles (Image 1). This will help avoid having any partial tiles in the doorway.
Measure the span of the tiles in the doorway (Image 2), then transfer that measurement to mark the span at what will be the end of the row — the cement board where it fits flush against the tub. Then use a chalk line to snap a line, parallel to the wall, to serve as a guide for laying out the first section of tiles.
Lay out a row of evenly spaced tiles along the chalk line from the edge of the doorway to the tub. Unless you're lucky enough to get an exact fit, the last tile in each row (where the row meets the tub) will need to be cut to fit. An electric wet saw is used to cut each end tile for a precise fit (Image 3).
The electric wet saw can cut through hardened clay tiles quickly and easily, using a constant stream of water to prevent the blade from overheating.
Before the installation of tile begins, determine the width of the grout joint (the width of the grout between adjacent tiles). As a rule of thumb, larger tiles require wider joints. For our bathroom floor, a 1/2" joint was used between each tile. To simplify layout, lengths of 1/2" scrap wood were used as spacers between tiles.
In the laundry room, the smaller tiles called for a smaller grout joint of 3/8".
After mixing the adhesive mastic, spread it on a section of the cement board using the smooth edge of the trowel. Then flip the trowel over and use the notched edge to obtain an even layer of adhesive over the entire section (Image 1).
Use the end of the trowel and apply adhesive to the back of each tile. The extra mastic helps ensure a strong bond between the tile and the floor. After applying the adhesive to each tile, position it in place (Image 2).
When setting each tile in place, work it back and forth to force the mastic layer into the cement board and the rough back surface of the tile.
Continue spreading mastic and placing the tiles, working on two or three rows at a time. Use the chalk line snapped earlier as a guide and the wooden spacers to ensure uniform distance between the tiles.
After the tiles are placed and the mastic is dried, begin spreading grout across the floor, making certain to get grout between each tile. Grout is applied using a specialized rubber trowel known as a float.
As the grout begins to dry, begin removing the excess with a damp sponge. Make several passes with the sponge to remove all of the excess.
Wait about 15 minutes, then remove the final layer of haze from the tile surface using a clean, damp sponge.