This tutorial shows raising baby up inside a panel carrier when the panel is too long, ensuring good airflow and free movement of the head.
This is important, as young babies have a large occiput (the round bone at the back of the skull) and if this is under pressure from behind, the head will tip forwards, pressing baby’s chin onto their chest and downwards into cleavage, which can present an airway risk. The fabric should never come higher than the bottom of baby’s earlobes, so they can move their heads freely. All the head support should come from the upper back part of the panel.