Make it darker and contrasting, using Image - Adjustments ? Curves
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
Add the same way in some places several stars' accumulations.