Oval Shaped: Oval face shapes can pull off just about any style, and this is true with bangs as well. Straight across, side-swept, blunt, choppy - you name it, you can wear it!
Heart Shaped: Straight across bangs work for you and can soften your angular face. Be careful not to cut them too short. Aim to keep them right at the brow for length; this will require you to see your stylist every two weeks for a simple bang trim.
Round Shaped: Round shaped faces need angles in order to diminish the fullness of your face. So, stay clear of blunt, straight across bangs and go directly for sideswept bangs to create dimension
Square Shaped: Make sure that you keep your bangs on the long side and go for a middle part or side-swept style of bangs. Short, choppy, straight across bangs will only emphasize the square shape of your face.
Keep in mind that most people have a combination of one or more face shapes and it is important to realize that and consult with your stylist on the best style of bangs for you.