Where should the harness straps be positioned on my child for rear-facing versus forward-facing use?

For rear-facing use, harness straps must be at or below the child's shoulders, with the chest clip positioned at armpit level. For forward-facing use, harness straps should be at or just above the child's shoulders. Always ensure there is no slack in the harness by pulling the adjustment strap until the webbing lies straight. (Page 7)