The following image explains the user interface for the PC version.
Choosing your base avatar (Leftmost icon at the right top corner)
You can choose the avatar that will form the basis of your new avatar.
Modifiable parameters include skin color.
Customizing the face (Center icon at the right top corner)
You can customize the hair, outline of the face, eyes, irises, eyelashes, eyebrows, nose, and mouth.
Hair
You can customize hair style and color.
Facial Outline
You can customize the width of the face, the size of the cheeks, location and size of the chin.
Eyes
For eyes, there are parts you can select. You can customize the vertical and horizontal location and size of the eyes. From version 2.4, you are also able to change the tilt of the eyes.
Irises
You can select from parts.
Eyelashes
You can select from parts.
Eyebrows
You can customize the horizontal and vertical location, depth, and size.
Nose
You can customize the direction, width and height of the nose, and adjust the bridge of the nose.
Mouth
You can customize the vertical location and width of the mouth.