Draw a simple horizontal guideline for the mouth placement
Sketch a light curve for the upper lip
Add a softer, wider curve for the lower lip
Connect the corners of the lips gently
Adjust the shape to match the expression you want
Refine the outline with smoother, cleaner lines
Add a small shadow or line between the lips if the mouth is slightly open
Erase any unnecessary guidelines
Add subtle shading to define the lips if needed