If you look closely (and I DO mean eyes right up as close as you can focus - get a magnifying glass to be more apparent) at any printed magazine, you'll see the very pattern that is on the lower guy's jacket.

I think in reality it's just a darker color.

I haven't tried this, so this is just a guess, but I'd start with a mild toned color (they seem to have a very pale dull cyan - or this could also be the result of ink-bleed during cheap printing - don't discount that), and use Levels Adjustment Layers - clip the White, then invert the mask (at which point it should be solid BLACK). Then grab your paint brush and paint WHITE where you want the shading to be - big soft brush will give you the soft edges, like for their hands, and hard brushes will give you the surface shading of the lower guy's cheeks.

You can lower the opacity of your brush for painting to layer it as much as possible, and toggle back and forth between black and white to take away, add more, take away, add more - incrementally, and not 100% all at once.

You can also do multiple Levels Adjustment Layers - even with different colors added per channel - to build it even more, or for different areas of the image rather than 1 Layer for everything.

I hope this makes sense and helps - good luck and have fun!

-Lew