Create the Mortar Preslope

• Frame in the shower with wood on the sides coming up eight to 10 inches from the bottom, and an underlayment of five-eighths-inch cement board on the bottom. Cut your hole for the drain and install it, letting the adjustable flange rise up out of the floor. Put down metal mesh made to increase mortar strength. Mix and lay your mortar about one-half inch thick around the drain hole, and sloping up at a ratio of one-fourth inch per foot toward the walls on all sides. Your hardware store can provide specialized measuring tools to help you get the slope right.
  
  

Seal and Topcoat the Floor

• Lay a layer of thick vinyl shower floor liner over the dried mortar base, stapling it about six inches up the wall on all sides and sealing it around the drain with shower-liner adhesive. Make sure to leave the ``weep holes'' in the drain unobstructed (these are sub-surface holes in the sides of the drain that will guide in any water that seeps though the topcoat of mortar). Lay the topcoat of mortar around the edge of the drain at a depth of about 1 1/4 inches, and then cover the rest of the floor with it, sloping upward with the presloped floor. Get the topcoat of mortar as smooth as possible.
  
  

Tile and Grout

• Tile the topcoat layer as you would any other surface, dividing the floor into four sections and tiling out from the middle to the edges. Since the shower hole is at the center, measure out from it to determine where the tiles would fall if they met at the center, and cut the tiles around the drain with a wetsaw at that position. Lay the rest of them off the first ones, using thinset mortar and cutting the pieces at the edges of the floor by the walls as necessary. Let them set, then grout the lines. Make sure to seal the grout with a clear liquid grout sealer after it dries. Set the drain down onto the surface, caulking under and around it.