The basic idea is to add some brightness and reduce the saturation in the highlights areas of the skin.
If the highlights all have roughly the same luminance, then you can construct a fairly sharp cutoff luminance mask. If not, you will have to dodge and burn the initial luminance mask to get the effect in the exact areas you want.
Next, you use the mask you just developed to mask a vibrance / saturation adjustment (to decrease the saturation in these areas), as well as masking a curves or a levels layer (to increase the brightness in these areas). Typically, performing only the brightness adjustment won't be quite enough, but it's a good first step.
Some people try to use PS's "plastic wrap" filter to accomplish this, but personally, I don't think the effect comes out as good as doing it manually.
Tom M