Paint.NET Eye Colorization - By Etain
Okay, this tutorial works best with real people (or artwork with human eyes) and it probably won't look as good with anime styled eyes. But you're welcome to try.

1. Open up your image. I used one of Olivia Lufkin. Duplicate the layer.



2. Zoom in as much as you can so you can see the entire eye on your screen. Click on the elliptical select tool and use it to create the selection for the eye. Now, when you're done with the first eye, go the the second one. Click on CTRL while making the second selection.



3. Now, go to Adjustments and then Hue/Saturation. A dialog box should come up. Play with the settings until you find something you like.



4. After doing that, you're pretty much done. But, in my picture the eyes had a weird yellow lighting. If you get that, you can just erase the yellow lighting while still being on the duplicated layer.



And that's it! You're done! (:

End result:



I hope this tutorial helped you. :D This tutorial was made by ETAIN.