Open the door
Check the knob for a visible set screw
Loosen the set screw with an Allen wrench if present
Pry off the trim plate or decorative cover with a flathead screwdriver if needed
Remove the screws holding the knob assembly together
Pull both knob halves away from the door
Remove the latch plate screws from the door edge
Slide the latch mechanism out of the door
Keep all screws and parts together for reinstallation or replacement