First, start off with an image (256x256) and pick a color (or two) I picked two just because multi-color eyes make it more interesting. Make the whole image the color your picked (or use a gradient for the two colors, like I did)





Now; to add a little texture - Add a new (transparent) layer and go to Filters > Render Clouds > Solid Noise. Fool around with the settings a bit and press Ok. Now there should be a black and white cloud-ish looking layer. Set that layer as Overlay; now it looks like it has some texture to it. This is how mine looks so far:





Now, to make those lines in the eyes; this is the coolest part because you never know how its going to turn out! What you do now is go to Filters > Render > Line Nova. Again mess with the settings a bit; what I like to do is set the Number of Lines to 200; Sharpness at 1.0 offset radius 40 + and the randomness, is random everytime I do it. Make sure your Foreground color is BLACK and then click ok! The lines should appear in a random order, different lenghts and all. It doesn't matter how close or far to the center they are, but if they're too close together it will look weird.





Alright, so after you got all your lines, set that layer to overlay as well (or whatever you think looks right; fool around with it!) Now, you need to make it to the side of a normal iris; with a pupil and everything. I use a template that was provided by Lollirot in her eye tutorial. Do whatever you need to do to get it down to that size (that fits in the completely white circle) or less. Mine is a bit too big actually, but thats fine I can always make it smaller.





And this will be the part where I let go of your hand. Tweak it yourself. Add shadows, the pupil (of course) add shine, burn it, add sparkles.. whatever. This is one of the things I came up with:





Questions are allowed, ask away!