From 
Image 1 of 15
1. Mark the tub wall lengths on the cement board
and score one side with a utility knife. Snap at the line and cut the
fiberglass mesh backing, just as you would with drywall. Smooth ragged edges
with the knife or drywall rasp.
Image 2 of 15
2. Fasten the cement board to the studs with
special 1-1/4 in. screws (or 1-1/2 in. roofing nails). Keep fasteners 1/2 in.
from the edges, and install nailers in the corners if necessary to ensure
adequate backing.
Image 3 of 15
3. Measure and mark the hole centers, then use a
compass to trace them. Cut the spout and shower head holes with a 1-1/4 in.
carbide-grit hole saw, and larger holes and curves with a carbide-grit jigsaw
blade.
Image 4 of 15
4. Tape cement board joints with special mesh
tape. Mix a batch of thin-set mortar and cover the tape with one thin
coat.
Image 5 of 15
5. Mark level and plumb layout lines. Evenly
spread several square feet of thin-set mortar with a 1/4-in. x 3/8-in. notched
trowel held at about a 45-degree angle. Shim the first row about 1/8 in. above
the tub to allow space for caulk.
Image 6 of 15
6. Align the tile with your layout lines and push
each in firmly. Pull one off occasionally to make sure you’re getting complete
coverage.
Image 7 of 15
7. Scrape excess mortar out of the joints before
it hardens. If mortar oozes out above the tile surface, spread it a little
thinner by flattening the angle of the trowel.
Image 8 of 15
8. Set the fence to width and make straight cuts
with a diamond blade wet saw. Cut slowly. Smooth the cut edges of marble with
200-grit wet/dry sandpaper.
Image 9 of 15
9. Cut the hole for the tub and shower spouts with
the 1-1/4 in. carbide-grit hole saw. Use light pressure to avoid cracking the
tile.
Image 10 of 15
10. Start cuts near narrow edges with the wet saw
to avoid breaking the tile. Grind rough edges smooth if necessary with the saw
blade.
Image 11 of 15
11. Clamp the marble to 1/2-in. plywood to provide
full support. Then cut through both with a carbide-grit blade. Cover the saw
base with painter’s tape to avoid scratching the tile.
Image 12 of 15
12. Lay in the special feature tiles following
layout lines. Use bigger spacers if the grout lines are wider, or tap in nails
to keep small tiles from slipping.
Image 13 of 15
13. Force grout into the joints with a rubber
float, scraping diagonally across the tiles. Wipe off excess with a damp
sponge. Polish off the light haze with a dry rag after the grout
stiffens.
