Gather tools and materials: tile, thin-set mortar, grout, backer board, waterproofing membrane, trowel, spacers, level, tile cutter, bucket, sponge, caulk, and safety gear
Remove old shower materials down to the studs or subfloor
Inspect framing and subfloor for damage, rot, or mold
Repair and straighten walls and floor as needed
Install a shower pan or pre-slope and waterproof base if required
Install cement backer board on shower walls
Tape and mud backer board seams with alkali-resistant mesh tape and thin-set
Apply a waterproofing membrane to walls, seams, corners, and shower pan area
Mark layout lines to center tiles and plan cuts
Dry-fit tiles to check spacing and pattern
Mix thin-set mortar according to manufacturer instructions
Apply thin-set to a small section with a notched trowel
Press tiles into the mortar with spacers between tiles
Check tiles for level and alignment as you work
Cut tiles to fit edges, corners, and fixtures
Allow thin-set to cure fully
Remove spacers after mortar sets
Mix grout and apply it with a grout float
Pack grout into all joints and remove excess from tile surfaces
Wipe tiles with a damp sponge after grout firms up
Allow grout to cure
Apply caulk at corners, changes of plane, and around fixtures
Seal grout if required by the grout type
Reinstall shower fixtures and test for leaks
Clean the finished tile surface