Jon Stewart recently sat down with Terry Gross and offered up similar thoughts.
A comedian's first 15 minutes is typically about his life. Your first joke is usually who you are. "I'm a Jew who was raised in New Jersey" joke. And then you work through your family and you basically go through your entire history with them. And you sit and stare at them but they're not doing much. So you have to then spread out.
So your next jokes usually come from where you go on the road. So I've taken my act about being a Jew from New Jersey to Tennessee. Want to hear about Tennessee? And that's your next act. Your next act is about your life as a comedian.
And then when that's exhausted, you tend to turn your vision to the world. And that becomes your tableau for your career.
Of course, if you're an observational comic or do a character or whatever, it's a different path.
Stewart also mentioned what he learned doing the final set at 2am at The Cellar every night:
I learned the difference between impersonating a comedian and being a comedian. And that was my break, learning how to be authentic. Not to the audience, but to myself. I developed a baseline of not only confidence, but insecurity. I knew how bad I was and I knew how good I was.
Reminds me of Woody Allen's idea of being a funny person, not having funny material.