This tutorial was made in PSP, but should be translatable for PS.
I just made a new easy following tutorial.
Learn in 12 easy steps how to go from:
to
(This tutorial wouldn't suit all icons)
01. Start Sharpen the image.
02. Layers > New Adjustment Layer > Curves
- Channel: Blue: Input: 254
Output: 208
Layers > Merge > Merge All Flatten
03. Copy and paste the texture below as a new layer and set blend mode to Exclusion 100%.
Layes > Merge > Merge All Flatten.
04. Copy and paste the coloured image below as a new layer and set blend mode to Multiply 100%.
Layers > Merge > Merge All Flatten.
05. Adjust > Brightness and Contrast > Brightness/Contrast.
Brightness: 30
Contrast: 21
06. Layers > New Adjustment Layer > Curves
- Channel: Blue: Input: 253
Output: 216
Layers > Merge > Merge All Flatten
07. Duplicate the base layer and set blend mode to Soft Light 100%. Duplicate again.
Layers > Merge > Merge All Flatten.
08. Image > Greyscale. CTRL + C and next press CTRL + Z (Undo Last Command).
09. CTRL + L (Paste as new Layer). And set blend mode to Lighten 100%.
Layers > Merge > Merge All Flatten.
10. Duplicate the base layer and set blend mode to Hard Light 100%.
11. Layers > New Adjustment Layer > Hue/Saturation/Lightness
Saturation: 44
Hue: 0
Lightness: 0
12. Layers > New Adjustment Layer > Curves.
- Channel: Blue: Input: 253
Output: 211
13. You're done ! Good luck and Enjoy ! =)