Good tutorial!
Since I am a professional photographer and editor...let me give a few more tips on PS.
You can use the select rectangle set to circular in the tool palette to select the face and then you right click on that and select "feather", pick a number like 50 pixels. Then you can adjust the brightness and contrast of the face...the feathering allows the adjustments to be more subtle and the procedure is a lot easier than using the magnetic lasso. Believe me, I use this hundreds of times a week in my photo editing and it makes life a lot easier.