The first thing you need to understand, is that courage is sexy. So it’s going to take courage to be more confident, and to be confident at anything requires skill, competence.
How do you get competence?
You practice, and how do you practice? You start. How do you start? You have the courage.
So you don’t go out and talk to the hottest chick in the bar. First of all, you’re probably not going to meet her there anyway, you’re probably going to meet her at a coffee shop, so just disregard the bar thing. But start with something that’s manageable, a little bit out of your comfort zone. If you are super shy right now and you have a difficult time making eye contact, then start practicing making eye contact with people in general. Not hot girls, just normal people.
Start by saying hi and smiling. Whatever it is that is a little bit beyond your comfort zone, start there, get really good at it and then move to the next step.