sorry nobody's answered you but I'll do my best *cracks knuckles*. It's good what you are doing when he sits by giving him the treat he will eventually figure out that it's more rewarding than jumping. It's also important that you make jumping up useless to him. He's jumping to get to your face, as puppies wolves lick their parents faces when they arrive home to greet and make them regurgitate food. Although your dog might not be expecting the same exact thing it is an instinct and your dog thinks these are proper greeting manners.
You can try putting him on his leash and sticking it under your foot so when he jumps the leash holds him down. If he trys and at any point ends up in a sit make sure he gets a treat for sitting.
What I would do is something that may get you some scratches so where long sleeves and maybe some padding
Come inside and make sure your pocket has lots of treats in it. As soon as he jumps on you turn around (if you turn so you are facing and against a wall you may keep your balance better, plus that will prevent him from running around you and finding your front). He may continue to jump at your back so cross your arms against your chest and wait until he stops. As soon as he does give a treat without turning around. If he stays down turn around and give him another treat. Ask him to sit, if he does then treat him again, give lots of praise and hope he continues being good. If he makes no attempts to jump again in this session then walk into your home and get out of the entrance. In another room you can let him lick your face if he still wants and you can play with him for being such a good boy (If letting him lick your face will cause him to start jumping once you stand up then don't let him ever lick your face, or if you just don't like him licking your face then don't do it).
Most likely things will not go that smoothly. He will jump you will face wall, he'll stop you'll give treat, turn around and give the other treat and then he'll jump again. If that happens then repeat the steps again. At this point he does not need to be sitting to get the treat, he simply must not be jumping. Do this over and over, until he gets to the point where he jumps, you face wall, he stops, you hand treat, then turn around give treat and he still has not jumped. That is when you will say sit and then give the third treat for sitting. If after that he jumps again then you will repeat the steps again including this step, turning around when he jumps until after giving the treat for sitting he remains there (or at least does not jump). At this point you can end the session
If the session only lasted a couple of minutes and he picked up on it with ease then once he sits and gets the treat and remains not jumping you can kneel down and pet him and give lots of praise and stand up. This will most likely make him jump.
If he does not jump up then give him a treat. If he does jump then repeat the steps as above until he settles and you can get him to the sitting step again without him jumping after the treat. Then end the session.
If the initial session (you did not kneel down) lasted a long time don't kneel down and make him jump again. That would be moving too fast for him.
Work through this for a few days, a few sessions a day. You will be able to phase out the treat he gets before you turn around pretty quickly (that treat was used do that he knew getting off of you was good enough, since as soon as you turned around you were likely to be jumped on, once you will be able to turn around with out being jumped on you can remove the treat before you turn around). The next treat you can phase out is the one after you turn around. That is because you will get to a point when you don't have to turn to the wall in the first place. If you can walk in and he does not jump then you will give the treat for not jumping in the first place. Then tell him to sit and give the second treat. Later you will discontinue the use of the treat for not jumping in the first place and only give the treat after you tell him to sit. Once that is used for awhile he will pick up the fact that he gets a treat only after the sit takes place and do it automatically. (All the above will take place over weeks or months depending on the dog, so don't rush your dog if he is having trouble!)
Once he figures that out then you will have trained him not to jump. he will still need to be rewarded for sitting for a long time and the sit will be automatic for him every time. Once you are 100% sure he will always sit when you come in you can phase out treats by giving them sometimes and all the other times giving him praise. At some point you will not need treats any more but you should always praise him some of the time with petting.
If you would like him to learn an actual command with this then use the word "off" (not down unless you use a different word for laying down). Start using it when your dog starts to stop jumping as soon as you turn around. That way you will say "off", turn and he will stop, then get a treat. Th command is not necessary but can be helpful for future if he jumps in different situations on different people.
Well I hope that all made sense. If it did not just highlight an quote whatever you don't get and I'll re-explain. I hope this was helpful and hope it works for your dog. I know we had success with it with Max and I wish you luck!