No one has taken you up with tips and critique yet, so I'll make the comments that others might start with...
If she's still available (someone you know, probably?) shoot this again and make sure you nail the focus on her eyes. This one is soft where it should be sharp. It looks like she has nice eyes -- show them!
And, I'd suggest cropping in from the right; there is more open space there than you need.
Just comments for starters,
Mark
Sharper focus on the eyes, increase the black level and a little on the contrast would be my main suggestion for what that is worth. The portrait is a bit to 'hazy' for my taste. If the lips would not naturally be a little more red (dark) I would suggest to experiment with a touch of makeup. The above suggestions may emphasize small imperfections on the chin - these are temporary and therfore I would remove those to reflect a more fair permanent image of the person. Frank
