original by Fabrice Gibelin

I tried playing with image with only minor changes. However, these methods could be used and adjust to taste.
1. I touched out a little of the sidewalk "litter" before beginning
2. Added a Curves adjustment layer and set black point and white point. I have my black dropper set to 20-20-20 and white at 240-240-240. (Scott Kelby recommendation) This seemed to boost the contrast a little.
I didn't make any change to the curve, but with an adjustment layer it is easy to experiment and edit.
3. Added a new layer, Overlay, 50% gray. (Hold down alt key while clicking the New Layer Icon, then choose options: Overlay and fill with 50% gray) Used the white brush at very low opacity (about 2%) to slowly paint in some selected highlight areas: whites of eyes, lips, cheeks, areas of arms and legs. Used the black brush to darken irises and pupils of eyes. Could also work on dark shadow under left eye to be a little more flattering.
I tried making an animated gif of my 3 layer image. Don't know if it helps or not. It is large file with only 256 color, but it was a good practice exercise with Image Ready.