Latch Checklist

Signs of a good latch
Your baby’s mouth is open wide with lips curled out.
His chin and nose are resting against the breast.
He has taken as much of the areola as possible into his mouth.
He is suckling rhythmically and deeply, in short bursts separated by pauses.
You can hear him swallowing regularly.
Your nipple is comfortable after the first few suckles.

Signs of a bad latch
Your baby’s head is not in line with his body.
He is sucking on the nipple only, instead of suckling on the areola with the nipple far back in his mouth.
He is sucking in a light, quick, fluttery manner rather than taking deep, regular suckles.
His cheeks are puckered inward or you hear clicking noises.
You don’t hear him swallow regularly after your milk production has increased.

http://www.healthychildren.org/English/ages-stages/baby/breastfeeding/pages/A-Breastfeeding-Checklist-Are-You-Nursing-Correctly.aspx