This tutorial is probably one of the easiest way to change eye color. First thing you need to do is to go to this link http://www.brushesdownload.com/bfile.asp?id=3113 and download the Contact Lense PS Brush. After downloading, here are the steps to follow.

STEP 1: Choose “Brush Tool”

STEP 2: “Right Click and load the Contact Lense PS Brush.

STEP 3: Create “New Layer”

STEP 4: Change MODE to “Soft light”.

STEP 5: Adjust Opacity.

STEP 6: Point Contact lense PS brush on eye lens.

STEP 7: Use “Eraser Tool” to remove excess brush.

Then it’s done!

Here is the result: