good advice Zoe.
Also when people come over, put him on a leash so its easier to enforce the lesson not to jump. Everyone has to behave the same around him though.
What I mean is all visitors, everyone has to use the ignore method at all times with him otherwise it won't work. Warn friends etc that you are training him, and that it would help if they do what you are doing in regards to getting him out of the jumping.
Does he have a place thats his? Like his own bed special spot where he can go to if needed? Once you've got the jumping under control, and during the training, you could also teach him to go to his bed, crate, or whatever is his.
It's good for them to know "go on your bed" or go on your mat etc, in circumstances that you might need them secure and out of the way. Mine do the meet and greet thingy when visitors are here, then basically are quite happy to go off to their beds