Line the top track up along the exterior of the patio door and mark where the holes on the track are located. Pre-drill the marks with a drill and bit and set the track back up into place. Insert screws into the holes to hold the top track in place.
Tilt the patio screen door and slide it into the upper track. Lock it into place and set it into the interior bottom track, which is already built into the door. Screw the supplied brackets onto the top of the screen door on both sides.
Slide the first door back and forth to make sure it is working properly. Install the second screen in the same manner into the outside roller track and lock it into place. Slide it back and forth to ensure it is properly operating.
Adjust the screws at both the top and bottom of each screen by loosening or tightening the screws with a screwdriver until they are sliding properly.