For most submissives, humiliation is erotic. Humiliation weakens him, and when he is weaker, he has less willpower and is easier to control.

But it isn't good for him to be weaker, and you don't want him to be weaker. So the issue for caring domination is satisfying a submission without humiliating him or making him weaker.

Punishment can also be erotic but weakening, perhaps when it points out his flaws or when he fears it. If you punish, be PERFECTLY CLEAR it is just a game. Do not punish him for his errors or faults, punish him for something obviously silly. If possible, choose a punishment that benefits him.

What about doing something embarrassing? The test is how he will feel about it in the future. If it is just a game, or something that actually makes him stronger, he will not feel bad or guilty about it. If in the future he feels humiliated, embarrassed, or guilty, it wasn't a good idea.