Put on safety goggles and work gloves.
Attach the handles and hinges to the predrilled holes in the door with a screwdriver.
Place shims on the tub or floor. The glass can rest on them while you are installing it. The shims ensure that the glass will have room to sweep easily along its bottom edge once it is installed.
Place the first door into position with the aid of a helper. Have the helper hold the door while you mark the tile with a pencil for drilling holes for the hinges.
Place the door carefully out of the way. Then drill your holes with a masonry bit.
Insert wall anchors into the holes and hammer them in. Cut off the protruding ends of the wall anchor. Place the blade of a utility knife flush against the tiles on top of the protruding anchor and then strike the end of the utility knife with a hammer.
Set the hinges into place and screw them in with a screwdriver.
Lift the door into place and tighten the screws by hand. Do not tighten them all the way down yet with the screwdriver because you may need to adjust them once the shims are removed.
Remove the shims. Open and close the door to ensure that it swings open smoothly and then tighten down the screws as needed.