Search for an enclosed spot such as a closet. Closets are ideal spots to hang a laundry bag because they are out of sight, they hide odors, and you can hang the bag from the clothes rod.
Find a convenient door if you can't find an enclosed spot. The back of a door that stays open most of the time is a good alternative because it hides the bag.
Hang the bag. Hanging laundry bags have a hook at the top that looks a lot like a clothes hanger.