The mouth and lips seem to give people all kinds of fits when they try to draw them. I think that the cause of this frustration simply stems from the order in which they approach the lips. You see, most people work from the “outside – in”. I think that it’s much easier to draw realistic lips and a mouth working from the “inside – out”. In this sketchbook challenge, we’ll take a look at drawing a smiling mouth.
Step 1 – Draw the Inside Portions of the Lips
First, we’ll draw the lines that make up the bottom of the top lip and the top of the bottom lip. You can definitely follow along with this step by step and draw what you see in each step here, but it is also advisable to grab a photo reference or better yet – a live person to draw from. You’ll need to closely observe your subject in order to draw the lines that are needed here.
Step 2 – Draw the Outside of the Lips
Now that the inside of the lips have been established in the drawing, we can turn our attention to the outside lines of the lips. Here again, these lines will be slightly different according to your subject.
Step 3 – Align the Teeth
With the lips in place, we’ll next align the position of the teeth. Since the mouth here is slightly turned to the left, it is especially important to locate the midpoint of the teeth. I’ll do this with a slightly curved line down the middle. I’ll also define a line where the top row of teeth and the bottom row of teeth meet. Here again, this line is slightly curved.
Step 4 – Draw In the Teeth
Since we have a good idea of the location of the teeth inside of the mouth, we can now add the actual shapes of the teeth. For most people, the top row of teeth will overlap the bottom.
Step 5 – Finish the Drawing
All that’s left to do now is to finish off the drawing. Be sure to darken up the corners of the mouth. You may choose to go over your lines with a darker medium to enhance the contrast. 
