To get an accurate eye first draw the space around the eye. 

(the negative space)

           Drawing the space around the iris will show the true shape of the iris.  

Stay away from drawing the whole iris. It will give you a surprised look.

Usually there is a bit of coverage of the iris by the top lid. Also the bottom lid often touches the iris.

 Unless of course the person really is surprised.  

Lashes-

     The lashes follow a fan pattern. straight in the center curving outward as they reach each side.  

Look at the lashes as a whole first..try and get that shape in. Sometimes you don’t need much more than that.  

If it needs more detail then the lashes generally fall in small clumps that form shapes (almost like small triangles).. a few lashes may stick out here or there. Once again it is not necessary to draw all the lashes.

There is usually a bit of a shadow on the top of the iris, caused by the upper lid. Then the darkness of the pupil in the center. Most times (But not always) there is a spot of light reflecting in the person’s eye. Sometimes I add this even if there is none to give the person’s eyes life.

The power of shape. 

To show how you can capture the feeling of any eye without drawing what is typically known as an eye shape, I present the following example. If you look for shapes and draw those shapes now matter how crazy they may seem it will give you the illusion of an eye.