If your character wears a specific type of uniform, has a visual deformity of some kind or requires some other unique feature, research it. If you want your character to look like a Japanese schoolgirl, look at samples of traditional school uniforms. If your character is in the military, look at military uniforms in different countries. Look at different facial features across anime characters and determine which are most popular. For example, many characters have almond-shaped eyes while others have cat eyes or very round eyes. Look at these facial features and determine what traits they imply. Someone with cat-like eyes is typically shrewd and cunning while round eyes signify youth.
Exaggerating one or two features helps keep your character memorable and easy to recognize. You may want to exaggerate the size of the lips if your character is sensual or the width of the shoulders if your character is strong, but always try to remain within the confines of the traditional anime character. Eyes are typically large while noses and mouths are small. Most characters have lanky bodies while some female characters are more curvaceous.
In many anime series, hair serves as the defining characteristic of a character. This proves especially true if several of your characters wear the same clothing due to uniforms. Hairstyles vary from an average bowl cut to long flowing locks to gravity-defying up-dos. Keep the hair of your character signifying of his personality. A strong man may have short, military hair while a bad boy has long, shaggy hair. A modest woman may keep her hair in a tight bun while a wild woman has long hair. In most cases, anime characters have straight hair.
If your characters do not wear a uniform, differentiate them further with their clothing. Though you want to keep clothing appropriate to the circumstance and time period, you want to exaggerate slightly. School children may wear especially bright patterns or they may each have different ties or bows. A fighting character may wear a long robe with an intricate system of ties and ribbons. In most cases, clothing and accessories signify personality. An artistic character may wear a simple dress and carry paintbrushes while a biker wears a leather jacket and boots.
Color helps create contrast while depicting personality. Good characters tend to wear lighter colors while evil characters wear black, gray or red. Green signifies growth while blue signifies peace. A cheerful character may wear bright colors while a somber character sticks to darker hues. With anime characters, you can take great liberty with hair colors. Though traditional hair colors are common, you often find other characters with hair in every shade of the rainbow. Quiet characters tend to have lighter hair while bold characters have matching, bold hair.