2. Greet your dog on his level! In addition to waiting to greet your dog, you should also greet him in a stooped position, so that he doesn't have to jump up to greet you. Additionally, if you wish to pet or cuddle your dog, do so on his level. This removes the need to jump at any time. PRAISE HIM for not jumping. If he jumps, use the "Off" command until he stops.
If a dog is stressed or afraid, their demeanor and typical behaviors will change. If you see this in your dog (or really any dog you know) you should step back and check on your dog. Are they hurt? Did a new dog come around they don’t know? Has the weather changed? Is it hot outside? When was the last time they had a chance to go outside to pee or poop?
Before you answer the door and welcome guests, clip a leash on your canine, preferably to a front-clip harness or head halter, so that he can be controlled in a manner such that he cannot greet if he jumps. When your dog is calm, with all four paws on the floor — which may take up to a few minutes for more excitable dogs — allow him to approach guests and say hello. If he jumps, gently turn and lead him away; wait for calm behavior before approaching again. For particularly excitable dogs, another option is to remove the dog to a contained area before guests come in. An exercise pen or baby gate is adequate containment for many dogs. If you have an athletic or large dog that can easily scale a gate, use a crate or move him to a room with a closed door. Once your dog calms down, clip on his leash and allow him to come out and greet your guests.
Paying attention to a dog only when all four paws are on the floor can work well, if jumping isn’t well entrenched and if everybody who deals with the dog follows the rules. Unfortunately, much of humanity will get busy undermining you. “I don’t mind your puppy jumping up,” they say, while you tear your hair out. Or they get all disciplinarian, maybe kneeing the dog in the chest. That is not only mean but counterproductive, because dogs often respond by trying to appease. Since humans are usually taller than dogs, reaching our muzzles to lick them involves jumping up.