How to Draw a Pair of Eyes
Start your eye with a curved line. You can use just about any kind of curved line as long as the bend in on the top. The picture above shows 2 different versions. You can play with this line to create different effects and aspects to your character.
When you look at most people (Unless they hold their eyes wide open all the time) the tops of their iris' are hidden behind their top eyelid. Draw a circle coming out from your curved line. If you are going to draw the rest of the character, you would go ahead and sketch the rest of the face and figure at this point. The curved line and the circle is enough for you to get the idea of the proportion for the rest of the figure.
Draw a little bubble on the iris. This bubble will not be colored in. It will serve as a reflection of light bouncing off the eye. Without that reflection, your character will look hollow... unreal.
Add the pupil. Think about where your character is. If they are outside in the sunlight, the pupil will most likely be small. If they are in a darker situation, their pupil will be open and very large. Fill it in solid black. There isn't a variation in this. All pupils are black.
Add shading to your iris. Think about the color of the eyes. If you are drawing in pencil or black ink, the lighter the color, the lighter the grayscale tone. If you are coloring the image with colored pencils or paint, the options are endless. Play with the color of the eyes. There is a shadow at the top of the iris next to the eyelid. This will give the eye depth.
A lot of people forget to add the tear duct. Everyone has one. They are often overlooked. Add a little curve closest to the nose.
Add the bottom eyelid. It is a curved line that passes below the bottom of the iris. It's simple enough.
Now that you know how to draw one eye, try drawing both eyes. The trick is getting them to look proportional. They are pretty much exactly the same, except the tear ducts are on the inside closest to the nose.
When you have mastered drawing the eyes, try adding shading around them. Also remember... Where there is an eye, there usually is an eyebrow.
If you think of any other tips for drawing eyes, please feel free to comment.
How to Draw Eyes Videos - Tutorials by other Artists
The following videos are some of the most amazing examples of people drawing eyes that I have ever seen. I like my simplified way of drawing eyes, but if you want to get more photographic than what I have shown you, then watch these people very closely and learn as much as you can.
How to Draw Books - You should have one of these on your bookshelf
I love drawing books. I don't ever pay full price for them. I usually buy them at used book stores or in the discount section at the new book store.