When working with slate, be sure to open several boxes and mix the tiles, because there are dramatic variances between the pieces.
Follow the manufacturer's instructions to mix the mortar. Use a liquid additive instead of water, and mix it to a peanut-butter consistency.
Set the first row of tile on top of 1/4" spacers. Mark the height of the first tile, and make a level line to be sure the tiles are set straight.
Back butter the tiles with thinset using a square-notched trowel. Place spacers in between to ensure an even grout line.
Measure the opening and transfer those measurements to the cement board. Use a square to be sure you make a straight line. Make six to eight scribes along the line with a utility knife, and then snap off the excess.
Set the board in place and secure it with cement board screws.
Find center on the wall and use a level to extend the reference line. Mark for the height of the diverter, and use the provided template to trace for the cutout. Make a pilot hole with a 1/2" drill bit, then cut the opening with a jigsaw.
Attach the copper stubs to the diverter before fastening it to the wall. Flux the fittings, then solder them together. Put Teflon tape and paste on the diverter, and screw on the supply stubs. Attach the diverter to a backer board with copper brackets.
The no-caulk drain assembly screws right onto the sink. Tighten it with locking pliers.
Use a jigsaw to cut the opening in the subfloor for the drain. Set two 2x4s on the ground to set the sink on so you don't pinch your fingers. Slide the sink into place, and remove the boards.
Find the stud and mark the slate for the location of the adjustable wall mount bracket.
Use a hammer drill with a tile bit to make the holes. Wetting the tile bit keeps it cool and allows it to go through the tile more easily.