Here are the steps to install a shower pan on a wood subfloor:
1. Level the floor and take measurements.
2. Cut out the floor and install the pipe and drain.
3. Apply a rope of plumber's putty or a bead of silicone caulk around the underside of the drain and push it into the shower pan.
4. Place the foam gasket, cardboard or paper gasket, and tightening nut from the underside of the pan, and tighten the nut by hand before using adjustable pliers to snug it down. Wipe away excess putty or caulk.
5. Mix the sand compound with water according to the manufacturer's instructions and apply it to the subfloor with a trowel to create a mortar bed.
6. Carefully place the shower pan in place, shimmying it back and forth until the rim lines up with the marks on the studs.
7. Seal around the edges with silicone.
