Turn off the shower
Cover the drain
Remove the old shower head by turning it counterclockwise
Use a wrench if it is too tight
Clean the shower arm threads
Remove old plumber’s tape or debris
Wrap new plumber’s tape around the shower arm threads
Screw on the new shower head by turning it clockwise
Tighten it by hand
Use a wrench gently if needed
Turn on the water and check for leaks
Tighten slightly if leaks appear