- 1). Lay a piece of 5/8-inch cement board at one end of the floor, in a corner. Mark the perimeter with a pencil, then remove the board. Use your notched trowel to spread thinset mortar over the marked area. Press the board back in place. Secure it with galvanized screws, sunk every 6 or 8 inches.
- 2). Lay additional cement board in the same manner, in staggered rows, covering the whole floor. Cut the pieces at the ends with a jigsaw as needed.
- 3). Lay fiberglass mesh drywall tape over the seams of the boards. Apply thinset mortar over the tape with your trowel (use the flat side, not the notched side). Get it flat and even. Let it set overnight.
- 4). Use a chalk snapline to divide the floor into four equal sections with two lines intersecting at the middle of the floor. Make sure the lines are 90 degrees to each other, laying a carpenter's square at the intersection and adjusting them as needed.
- 5). Apply thinset mortar over intersection with your notched trowel, covering a few square feet. Set tiles in place starting at the intersection and working outward toward the walls, spreading down more thinset mortar as needed. Put spacers between all the tiles. Cut the tiles by the walls as needed to make them fit, using your tile cutter.
- 6). Let the tiles set for 24 hours. Pull out the spacers.
- 7). Grout the floor by spreading the grout down with a grout float, forcing it into the lines between the tiles and scraping it off the surface. Wipe up the excess grout with a damp sponge.
- 8). Let the grout set for a week. Apply grout sealant over the grout lines with a small paintbrush.
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