Almost every difficult behavior is a message. It is your person's way of saying something they can no longer put into words. Applied Behavior Analysis, or ABA, gives you a simple tool for reading that message: the ABC framework.
A is the Antecedent, what happens right before the behavior. B is the Behavior itself. C is the Consequence, what happens right after. The behavior is in the middle, but the power is usually in the A. If you can change what comes before, you can often prevent the behavior entirely.
Common needs hiding inside hard behavior: comfort or relief from pain, escape from something too hard or overwhelming, sensory regulation, a need for connection, a need for some control, or an unmet physical need like hunger, thirst, or the toilet.
So instead of asking "How do I stop this behavior?", ask two better questions. What happened right before? And what might my person need right now? Then change the setup rather than trying to change the person.
This is the engine of the whole module. You become a detective, not a referee. You are not trying to win. You are trying to understand, so you can adjust the situation and help the moment go better for both of you.