The computer is a great creative tool as well as being a lot of fun once you get used to working with it. Frequently I experiment to see what I can come up with. Here I have created a couple of cartoon heads using only the Line Tool and parts of a typeface.
I begin by doing some simple shapes with the Line Tool.
Then I add a couple of letter "O"s for the eyes and the hair. A large "O" which was cut in half was used for the lady's hair and a smaller "O" for the bun. Her eye is composed of a stretched "O" with lines added for the lashes.
Next I added the eyes and mouths, finishing them off.
Here is one color version, I could try several more very easily.
A change of expressions by altering the mouths and his eyebrow.
Another change of expression. Try this and see what you can come up with, it's great fun and will help you develop your computer skills.