1. Open your image. I will used a grayscale stock photo, but you can use a color photo if you wish.
2. Grab you elliptical marquee tool
and select an area around the eye.
3. Next you need to enter quick mask mode, it is located on your tools palette under your color selection boxes.
It should make your image a transparent red except for the marquee selection you made, that's good that means your in quick mask mode.
4. Now using a hard edge brush and black for a color, zoom in and paint around the eye so all that is selected is the eye itself Before:
After:
5. Now you want to return to normal mode.
After returning to normal mode you should be left with the original image and the selection around the eye.
6. Make a new layer.
7. Edit > Fill and choose "color" and select the color you wish to make the eye. Now if you used a grayscale or black and white image you'll want to set the blending mode of the filled color to "color", if it's a colored image you'll want to select "hue" as the blending mode. Note: to deselect Ctrl+D Final image:
