Measure the door opening
Choose the correct door size and swing direction
Remove the old door, if needed
Remove the old hinges and hardware
Check that the frame is square and level
Shim the frame if necessary
Place the new door in the opening
Mark hinge locations on the door and frame
Cut hinge mortises, if required
Attach the hinges to the door
Hang the door on the frame
Check the reveal and alignment
Adjust shims and hinge placement as needed
Drill and install the latch and strike plate
Install the doorknob or handle set
Test the door for smooth opening and closing
Secure all screws and hardware
Install trim or casing, if needed
Caulk gaps and finish the surface, if needed