To open the airway for an infant, follow these steps.
[1] Place the infant on a firm surface (table, floor, etc).
[2] Place one hand on the infant's forehead and gently tilt the infant's head backward very slightly.
[3] With your other hand, use your fingertip and gently lift the chin. Avoid pressure on the neck and soft tissue.
The infant's airway should now be open. You can listen and look for any breathing. If this does not happen, give care as needed (that may include five small rescue breaths or staring CPR).
Please take note that an infant's head needs to be tilted back far less than an adult's. Infants are fragile, so take care to be as gentle as you can in the situation.