1 Attach the mechanism
Follow the individual manufacturers' instructions to attach the counterweight mechanisms to the sides of the garage door.
2 Position door
The most difficult step in fitting the door is raising it into position in the frame and then temporarily holding it there with props and wedges. If possible, get one or two helpers to assist you.
3 Fit the tracks
Once the door is propped and wedged securely in position and then fixed to the frame, the tracks (if your door system requires them) are fixed securely along the interior walls of the garage at the appropriate height.