Ok this might be quite long....(and I might not remember it in the right order

)
1) LEVELS!!! SOOO important with portraits (I find). In photoshop, you press CTRL + L, and the histogram comes up. I moved the sliders until they matched the ends of the 'active' areas, (where the line on the histogram went 'up' at all) therefore overall lightening the image without doing 'brightness'.
2) Selectively selected (hmm...) the eyes, with circular marquee tool, and increase saturation and sharpening, in small amounts, so as not to make it look unnatural
3) Right click -> "select inverse", desaturate the rest of the face a *tiny* amount, because he was very red, and it made his overall complexion darker
4) Touch of sharpening on rest of the image, with the eyes still inversely selected (so they were not affected...)
Hope that helped or made sense....or made it look like I knew what I was doing

Glad you liked it!
Jack M