You should always make sure that you can see the baby’s face.  The baby’s face should not be covered with fabric, especially the nose AND mouth.

The sling should not form a ‘tent’ around the baby’s face, to allow free air exchange.

The baby’s chin should not be held down to the baby’s chest.  You should be able to easily insert a finger between  chin and chest.

If your baby is showing signs of labored breathing, wheezing or ‘whistling’ with every breath, especially while sleeping, then the baby should be repositioned.

It is  good to frequently touch and pat your baby.  This kind of stimulation has been shown to regulate an infants breathing and heartbeat.