What is the proper way to recline the Evenflo 4-in-1 Car Seat and how do I know when it's at the correct angle?

To recline the seat, lift up on the recline handle located under the front edge of the seat and adjust it to one of the three rear-facing recline positions. The seat is at the correct angle when the level line on the side of the restraint is parallel to the ground. This is critical because infants may have difficulty breathing when in an upright seated position—they must recline enough for their head to lie back comfortably and safely. If necessary, place a tightly rolled towel or small blanket beneath the front edge to achieve proper recline. (Pages 28, 33-34)