Teach appropriate alternative behaviors that help them get their needs met.
Help them learn words and other helpful ways to communicate (sign language, pictures, etc.).
Praise them for any attempts to communicate difficult emotions.
Practice “gentle touch” at times other than when the child is hitting or biting.
Respond positively when they seek your attention in appropriate ways.
Create the conditions for their best behavior: Make sure the child is not overly hungry, tired, or stimulated.
Read books together about dealing with tough emotions.