How do I install the kid seat on the Cargo 7?

The seat clamps onto the rails of the rear deck with four quick-release brackets. Set it on the deck facing forward toward the rider, line up the four brackets on the rails, and close each quick release, which should take some effort. Pull hard on the seat side to side, up and back to confirm it doesn't move. Adjust the harness and footrests so the rider's feet rest on them away from the wheel, and test it with the child in the seat. Put the center kickstand down when loading the child.