1. Crop your image.
2. Go to layer> new adjustment layer> curves
Point one: 100/93
Point two: 149/151
Point one: 129/124
Point one: 102/95
Point two: 141/145
Point one: 108/91
Point two: 147/149
3. Again layer> new adjustment layer> curves
Point one: 119/131
Point two: 142/161
Point one: 123/133
Point two: 136/154
4. Layer> new adjustment layer> levels
5. Layer> new adjustment layer> mix channel (sorry if it has different name, just i have russian version of Photoshop)
6. Layer> new adjustment layer> hue/saturation
Increase Master saturation as much as you want. I have +9.
That is all!
Another icons made with this tutorial: