To put yourself forward as someone good enough to do interesting things is, by definition, to expose yourself to all kinds of negative judgments, and as far as I can tell, the fact that other people get to decide what they think of your behavior leaves only two strategies for not suffering from those judgments: not doing anything, or not caring about the reaction.
Clay Shirky - A Rant About Women
Notwithstanding the title, this is a good read on self-confidence for anyone, irrespective of gender.