I don't consider myself an expert in just about any aspect of computer science / programming, but I'd like to start to share the bit of knowledge that I do have in a more public (meatspace) forum.

Anyone have any advice for getting started? I've reached out to my local Java Users Group and there are some Meetup coordinators I'm going to get in touch with. Do you have any general advice? Or particular websites for finding conferences / events which are soliciting speakers?

Any horror stories to make me less worried about my first talk?