Confidence is something that comes in time - I know that's not what you want to hear, but it's part experience and part growth and evolution...
At it's root is the acceptance of yourself as "OK the way you are" and truly coming to peace with yourself. It's' OK to appreciate, accept, and love youreself. In fact, it's a pretty crucial step. Our culture is pretty bad about that, but thankfully that's changing these days.
Here's something to get you thinking in that direction...
How to Get Over Shyness & Fear of Rejection to Get the Girl
And this one (it's older, but this stuff is timeless):
Is Shyness Keeping You From the Girl Of Your Dreams?