Start with two dots.
Add two more dots, slightly higher than the first two.
Add two lines, one above and one below.
Add two arcs extending up from the outer two dots.
Complete the lower lip. Go slowly and be careful about the symmetry.
Close the top lip by connecting the top arcs to the top line.
Add a u-shape between the two middle dots.
Connect the middle and outer dots.
Darken and extend the outer dots.
Add some basic shading and you're done!