Some very good points were brought up in this article. I have come across some other keys to increasing confidence as well!

1. If you are a shy person meeting new people, think as though you are meeting old friends. Surprisingly this works for me because it reduces the stress associated with putting myself out there, increasing confidence.

2. I have also found that the more I judge people, the less confident I feel. Letting people live the way they please will allow you to do the same mentally and make you feel more confident in your actions.