In this tutorial, you will learn how to create a cartoon eye with Adobe Illustrator. To start this tutorial, you don't needed to be a Illustrator expert. So lets get started. As usual, let me show you the final result of this tutorial,

1 First make this "so hard" outline of an eye.

2 Now make the eyeball using "Elipse Tool"

Every eyeball (except cartoon maybe) in this world if you look it from the front it'll be always shaped a perfect round, if you don't trust me try to trace it from a real frontal human photo.

3 As you can see the eyeball line is too big, that's why you need to make a path using "Pen Tool" to cover the overlaping part, and when you make new path ALWAYS use a different color just to make it easier.

Now to cut the overlaping path you need "Pathfinder" (to open it press "Shift+Ctrl+F9"), hold "Alt button" then click "substract from shape (Alt+clik to expand)".

4 Fill the eyeball with 2 any colors you want, so it won't seemed flat plus it saves your time (I chose magenta and black)

Use "Radial Gradient" for this matter

5 Make another round Path using "Elipse Tool" for the center and the highlight of the eye, and the color for the center of the eye should be black, as for the highlight it depends on the lightning of the background or surrounding, white is for normal daylight I suppose.

6 "Copy" the center path and paste it in front, DO NOT use normal paste (Ctrl+V), coz it will showed up on different place, and we need it on the same exact place.

After making the center path became 2 paths, you won't see it the difference unless you opened the layer window, there will be 2 round shapes.

7 Go to "Effect Menu>Blur>Gaussian Blur" and set the "Radius Parameter" then click "OK".
Now your image will look like following one,

8 Now make it bigger, if u can't make it bigger just by using "Selection Toll (v)" use "Free Transform Tool (e)", don't forget to press "Shift" so the path won't get distorted
And it'll look like this.

9 Let's add some shadow so it won't be Flat by using "Pen Tool (p)"

10 Arrange It to the bottom of the layer.

To arrange the path: hold "Ctrl" and press "[" to bring it down, and "]" to bring it up or drag it manually on the layer window. to bring it to bottom or to the top hold "Ctrl+Shift"

It's done, but i'm not satisfied enough, let's add more details on the eyeball.

See also