When installing a door lock, the keyhole should be positioned on the outside of the door so you can unlock the door with a key from the outside. However, the two sides of a lock assembly are a mirror image of one another, and any lock can be installed with the keyhole facing either direction. Any key-in-knob or deadbolt lock can be easily reversed if it has been installed improperly or you need to change the direction of the keyhole for any reason.
Unscrew and remove the trim screws from around the lock with a Philips screwdriver. Remove the trim if possible at this point and set aside.
Unscrew and remove the edge plate screws from the trim around the bolt with a Philips screwdriver if reversing a deadbolt lock. Pull the trim and bolt from the door edge and set aside.
Pull the doorknobs or lock trim apart and out of the door panel. Replace the knobs or lock cylinder on the opposite sides of the door panel.
Replace the deadbolt and edge plate. Replace the lock trim and all screws. Test the lock.