Despite what Darkendnight says, one cannot cause physical changes such as changing the color of one's eyes through the use of magic.
Just because one believes that they can is not enough, it still needs to be physically possible. As an example, one could sit in the garage all night believing your are a Chevrolet, but that won't make you an automobile.
If you wish to seem to have eyes of a different color I would suggest colored contact lenses.
I'm not 100% sure about that. Please hear my reasoning. I understand magic cannot make the physically impossible, possible, but, human beings eye colour is changeable. Geneticly. I have a friend whose eyes change very slowly over the course of his life. At birth they were green, became blue from photos I saw of him in kinder garden and were yellow for a while. They were grey recently but have been taking on a blue green colour recently. So it is possible for eyes to change colour. I do not think there is a way to overnightor even over a year change your eye colour, but iI don't quite think its impossible. By the same principals of magick that promoted healing by having the life energy from one person shared with another to increase the healing rate, I do believe that it could in theory be magickally possible. Not easy or maybe not doable in practical time, but I seriously doubt its impossible. If you don't agree I understand, buy I just wanted to chime in my thoughts as well, despite being quite the novice.
Shellfire, what we are saying is that eyes cannot change colour by magic! Eyes do sometimes change colour naturally. Most Caucasion babies are born with blue eyes. Some stay blue,some change, usually to the mixture known as "hazel". Photographs can be misleading, due to differences in the light source. In the elderly,eyes often "fade" in colour.
Nevertheless, Lark is telling it true; you cannot change eye colour by magic!