When drawing the mouth, bear in mind that they are different from each other, varying in size and format.

However, they are all built with a combination of straight and curvy lines.

By varying the shapes you can create many mouth styles. Feel free to explore!

You can think of a mouth shape as a bird flying towards you, with a shadow cast below. 

Is often a good practice to make the upper lip a bit darker than the lower lip.

This implies your character is being lit from above (most common light situation).

Remember to Increase the line weight on the outer corners.

The outer corners of the mouth kinda line up with the center of the eye socket.

Symmetry is your ally in building convincing characters, regardless the style and angle of your character.

Commonly, thin mouths without lip lines are instantly associated with men.

Women have more “colorful” mouths and often require a little more detail and volume.

Bright highlights over a darker mouth may suggest the use of a lipstick.