Your child under the age of two should always ride in a rear-facing car seat, and always in the backseat.
Front Facing Car Seat
You should keep your child in the rear-facing position as long as possible. She/he are ready for a front-facing car seat once they have reached the weight and height limit indicated in your rear-facing car seat.
Your child is ready for a booster seat once she/he outgrows the front-facing car seat based on height and weight indicated in the front-facing car seat manual. Children in booster seats should still remain in the backseat.
Keep your child in a booster chair until she/he is big enough to wear a seat belt properly. The lap belt should fit across their upper thighs, not their stomach. Also, the shoulder belt should lie snugly across the shoulder and chest and not across the neck or face.