If you're using photoshop:
1. Open the picture that you want to fix
2. Create a new layer
3. Grab the brush tool and set it for the exact number of pixels as the eye
4. Choose the color you'd like the eye to be, but go a bit darker than you'd think to go.
5. Place the brush over the eye and click once. You should have a circle of color now.
6. Make the layer either overlay or soft light, depending on the effect you prefer.
7. Create new layer
8. using the brush again, set your foreground to black and shrink the size to match the pupil only.
9. Click once over the pupil to make it completely black again.
10. Shrink the brush to about 1 or 3 pixels, depending. Make the foreground white and add a sparkle or two.
That should do it. Save and upload.
Before:
After:
