More Confidence:

Sometimes I look at GMB and wonder how on earth he became so confident. He exudes self-assuredness, so much so that it's a little on this side of pompous. I know that's often the case with teenagers.
Unfortunately, I was never like that at 15— or 30.
I have moments when I know I'm just as talented as everyone else, just as attractive and worthy, but that lasts only moments. Most of the time I surely think people must be thinking how boring I am, or how huge my ass is, or how I am not very ambitious. And I feel like shit. It makes me feel very average, in the very worst sense of the word.
The problem is that I don't really know how to go about gaining confidence. I think that if I become successful enough, then I will gain confidence. Or if only I made more money I would realize that surely I must be a clever guy. But of course I'm smart enough to know that kind of thinking gets you nowhere.
So, what's the secret to becoming a confident person? Does it just come naturally to some and those of us without it are out of luck? Or is there something like a 5-month, 5-step plan to being bold and confident?