1. Open your image in Photoshop. Duplicate it once. Select the duplicate image on your layer palette and set the blending mode to Soft Light. 2. Go to Layer > New Fill Layer > Solid Color. Choose a really dark blue. I use #070144. Set this Fill Layer to Exclusion. 3. Go to Layer > New Adjustment Layer > Levels. Slide the black slider to the right a little bit to increase the intensity of the coloring.