The steps are: double click on background layer and make it a normal layer then desaturate (image adjustment desaturate), make a duplicate image layer and invert (image adjustments invert), blend color dodge (white with black spots) filter other minimum, then touch up with airbrush or dodge tool.

Tutorials

• http://www.youtube.com/watch?v=LyNsb_9PUFU

Click on an image to see a larger version.