For ourselves it's window, seatbelt, exit. When we have kids in the car, it’s similar: window, seatbelt meaning your seatbelt, then your child’s seatbelt, push them out the window and then you exit the vehicle. Once everyone is out of the car you can collect the kids.
WINDOW, YOUR SEATBELT, CHILD’S SEATBELT, CHILD EXITS, YOU EXIT