If it already has plenty of d rings installed its nice to have an assistant when hanging. I instruct people when they pic up their rugs from me to use painters tape to mark the walls with the help of an assistant to make sure they put a nail at they exact location as the d ring as they hold the rug in place by hand, its also nice if you can locate a stud in the wall for the head, if not use a screw in drywall anchor (these are rated to hold 60lbs) as insurance if only drywall in head location.