The most common mistakes are a loose harness on the child, a loose installation in the vehicle, and moving the child to the next stage too soon. Just remember pinch, inch, pounds (and inches). If you can pinch the harness, it's too loose. If you can move the seat more than an inch in the vehicle, it's too loose. Keep your child in each stage until he or she reaches the upper weight limit (pounds) or height limit (inches).
To find out if you are using your car seat correctly, make an appointment with a local technician. Visit www.buckleupnc.org/local-programs-checking-stations to find a list of child passenger safety technicians near you. Safe Kids Worldwide has a variety of tips, videos and infographics to answer your car seat questions.