Tap the door's pivots into the pre-drilled holes on the door's edges with a hammer. Each door has two pivot pins and one locking arm. One pivot pin goes into the hole on the fixed door's top edge and the second pivot pin goes into the hole in the fixed door's bottom edge. The locking arm goes into the sliding door's hole in the top edge.
Lift the bi-fold door up to the closet opening. Tilt the door slightly and insert the top pivot pin into the pivot socket along the track.
Straighten the door out and place the bottom pivot pin into the floor bracket. Press down on the locking arm with your finger. Center the locking arm under the track and release it.
Close the door. Step back and look at the gap between the door and the jamb. If the door seems crooked, use a screwdriver to loosen the screw holding the pivot socket in place. Slide the pivot socket along the track until the gap between the door and jamb is even from top to bottom. Tighten the screw to secure the pivot socket in place.
Adjust the bi-fold door's height by rotating the bottom pivot. Lift the door so the pivot comes out of the floor bracket. Use your fingers to turn the pivot either clockwise or counterclockwise, depending on if you are raising or lowering the door. Lower the pivot back into the floor bracket.