Your parent talks with you about the rules, responsibilities, duties, discipline, manners, etc. If parents now in separate homes are still angry with each other, watch out for the crossfire. Notice if it looks like what you say about Mom in Dad's house and about Dad in Mom's house could get you in trouble. I feel she gets more attention than I do. It's important that kids recognize their feelings and talk to parents and stepparents.
Kids can teach, too.
Know that parents and stepparents are often confused about what they want from you. Kids need to have a part in making the home run. Ask adults what they want. Especially today kids can overwhelm adults with good manners and consideration. Know that often adults have high expectations about remarriage.