Measure the shower area and determine the drain location
Remove the existing floor surface down to the subfloor or slab
Install or verify a properly positioned shower drain assembly
Build and secure the shower curb if needed
Install a pre-slope mortar bed or sloped base toward the drain
Place and secure a waterproof shower pan liner over the floor and curb
Seal corners, seams, and drain connections with compatible materials
Protect the drain weep holes with gravel or spacers
Install a final mortar bed over the liner, sloped to the drain
Let the mortar cure fully
Test the pan for leaks with a flood test
Install wall backer board and waterproofing as needed
Finish with tile or another approved shower floor surface