Have you ever wondered how those models in the magazines have such a beautiful skin color? Me too, till this point in time I was using a separate layer in Color mode. However the colors improved, the results weren't that straight forward and clear as I wanted them to be.
And just yesterday I've found a way to do it much much better. The skin color is exactly I want it to be, and I have a lot of settings to adjust it to the point. And all of it in one layer, no mess, no fuss. All changes are reversible, i.e. non destructive! The image above shows an example of adding a tan to the person's face.

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The funny thing about this approach is that we start with creating an Hue/Saturation adjustment layer and turning the saturation off - no color whatsoever. You can see the resulting stack of layers in the layer palette on the right.

And the in the Layer Style dialog (below) we change two settings:

The first thing we do we set the color we want to have - via Color Overlay. The blending mode for the Color Overlay is Soft Light, you may try others, but this one worked best for me.

The second setting is about blending of dark areas for both layers. By holding Alt key drag the dark triangle under each slider to the right - it will open up the shadows, which the Soft Light blending mode tends to cast in total shadows.

And finally, we use a layer mask to apply the effect (skin coloring) to only the areas we want - the face and open skin areas.

The best thing about this approach is that you can change the color any time to whatever you want - nothing restricts you, you don't have to repaint the layer or use the brush again - a few clicks to pick the color and you are done!

What about the settings? Well, let's see: Opacity of the whole Hue/Saturation layer, three sliders in the adjustment layer itself, the color in the Color Overlay setting, then the blending mode and the opacity as well (within the same Color Overlay setting), and finally the blending mode for the adjustment layer along with all the blending mode settings (as in the dialog above). I think, it's more than enough to control every possible variation of the color and it's application.

If you are interested in a further steps of portrait retouching techniques, then read my article "Ultimate Makeup".