[mmv]

But don't hold yourself too much if you think you're not too knowledgeable about something to present about it.

You may be deterred by watching some talks where the presenter seems awesome and seems to know so much more than you. You don't have to be the top expert on a topic in order to know a few things worth sharing.

[davnicwil]

This is absolutely the case, and I think an important addition is that usually there's only a very small percentage of the audience who are already knowledgable enough about something to benefit from hearing a truly world-class expert talk about it.

Most people go to tech meetups, even very specific or niche ones, hoping simply to pick up a few tips or an introduction to something from somebody who used it in anger. You don't have to be an authority on something to just learn a few lessons from using it and pass them along.