Lip painting
The shape of the lips is an "M" shape in the upper part and a convex semicircle in the lower part. The two shapes form an acute angle, which can draw the outline of the lips. Finally, the lips can be colored to complete the drawing of the lips.

When you draw the outline of your lips, you can add some broken lines on your lips to reflect the thickness and shape of your lips, and draw highlights where your lips are raised.

After the thickness of the lip contour is drawn, you can color your lips. Lips can be directly colored in red, and the highlight position is directly left blank when coloring, so that the protruding position of lips can be reflected. When you draw lips, the lips are drawn.