Make it darker and contrasting, using
Image - Adjustments ? Curves (ctrl+m)
Cut it out along the eye's line with
Polygonal Lasso Tool.
Change the layer's type on Multiply. Take a ready brush now, imitating the marble veins and cover the entire picture with it. Cut the eye's orifice.
Change the layer's type on
Soft Light. Take the next instrument:
Brush Tool and picture with it many points of different sizes.
Apply to this layer
Filter ? Blur ? Blur. Copy it several times and blur out each of them, setting different radius with
Filter ? Blur ? Gaussian Blur.
Then apply to each of the new layers one more filter:
Filter ? Blur ? Motion Blur. Merge all the layers that we've got, making use of the next command:
Layer ? Merge Down (ctrl+e).
Add the same way in some places several stars' accumulations.