One of the most important things to draw well when working with a human character (or almost any character really) is the eyes. It is what gives your character life and helps them to show expression. There are many different styles of eyes that artists draw, but the basic anatomy and shape of the eye is fairly constant. 
I almost always begin by drawing out the entire eyeball because I think it makes it easier when adding the eye lids, and getting proportions right. I most likely won’t render it out in such detail right off of the bat as I have done here, but I just want the underlying shape and position of the eyeball to be clear.
Something to keep in mind, is how the eyeballs are positioned on the face. This is not a set in stone rule (especially when drawing cartoons), but it is a good general guideline to follow.
Here is a basic step by step example of painting a somewhat realistic pair of eyes.
My next post, I’ll get into more detail regarding expressions, and drawing with a more cartoon like feel.
artistic anatomy 