I've posted what worked for me before. It's rough. It uses aversion. When the kind, non-aversive methods didn't work I went to this to protect my 91 year old mother at the expense of the dog. A trainer showed us this at the request of another owner of a jumping dog. What breed was that other dog? Need you ask?
The Yank 'Em Down Method. Dog on leash, helper entices dog to jump, yank him enough to defect the landing on the person. Your goal is not to throw your dog across the room, just keep him off the helper. When you yank give your don't jump word. Ours is FEET (on the floor.) The little poodle mix ( not that little really) took one yank and no matter how the helper encouraged him to jump he would not. The other Lab took two yanks, Oban took three.
If you don't think you can gauge how much oomph to put into your yank don't try it. We had cushiony floor in the training room, so maybe do it on grass outside.
There are some advantages to this over other methods. For one the dog will pay no attention to those people, like my Mum, who encourage him to jump, knowingly or not. For two it works at a distance, it does for us. For three it's YOU the dog is listening to, not someone else.
About three months later Oban needed a refresher, just one yank. He hasn't needed one since. He was 8.5 months when we first did this in class.
I think it helps that Oban does have a word that allows him to jump on me or other people. HUG. There have been a few wayward jumps on strangers that for some reason said HUG out loud, of course he was forgiven for those.
If you try it let us know what you think and how it works. I'm sure you'll get lots of less rough suggestions, try them first. Good luck.