Turn off the water supply
Plug the tub drain
Inspect the spout for a set screw or threaded connection
Loosen the set screw with the correct hex key if present
Pull the old spout straight off the pipe if it is a slip-on type
Twist the old spout counterclockwise if it is a threaded type
Clean the pipe threads or pipe end
Measure the pipe length and confirm the new spout fits
Apply plumber’s tape to threaded pipe if required
Slide or screw the new spout into place
Tighten the set screw if present
Restore the water supply
Test the spout for leaks and proper flow