Think about whether your dog might be getting a reward of some sort in response to their behaviour, even though you may not mean for them to! For example, think about a dog jumping up on someone who tells them “no, get down” while staring at them and pushing them away. If the dog enjoys being looked at, spoken to and handled by people, then even this interaction can be rewarding. This means they’ll be more likely to jump up again despite the person thinking that they haven’t given any sort of reward at all!
In these types of situations, think about getting ready to guide your dog into making a good choice. For example, ask them to sit and reward this before allowing them to meet someone. In fact, if they like meeting people then getting to do so can be the reward for keeping their feet on the ground! You can think about using rewards within the environment to help positively reinforce good behaviour. For example, if your dog loves running off lead, then this can be a reward for walking along nicely on lead for a few paces. Think about all the things your dog enjoys and how you can use them to reward good behaviour, this will mean your dog learns how to behave in a very happy way indeed!