Very simple: after they exit the plane, tell them to walk in the same direction as all of the other passengers who are exiting the plane. Just after passing the security screening area (they will not have to go through security, but will walk to the right of the screening area), they should take the stairs down to the lower level. At the bottom of the stairs, they will have to walk straight through a norrow hallway. At the end of the hallway, they should turn right to the AA baggage carousels.