Frodo and Bilbo are allowed on the furniture, but they needed to know a solid "off" for various reasons. I taught this by taking one dog into my room and waiting. Soon, one of them would jump up on either my bed or my little couch. As soon as they did, I would turn away, make myself appear or sound fun, sometimes by holding a treat, sometimes by patting the ground, and say off. As soon as they got off, they got rewarded. And repeat.
So, once your dog knows that, you can simply say off every time you see him on. And if he jumps up when someone is on, simply have them ignore him, other than telling him off. Soon, he'll learn that getting off the couch actually gets him the good stuff, while being on doesn't get him any attention. It's kind of like when someone turns around and ignores a jumping dog. Take what they want and use it to your advantage.
G'luck!