Listening to yourself makes a HUGE difference, in my experience. I've gotten used to recording myself for things like singing lessons, and it's been perhaps even more beneficial to replay the casual conversational exchanges with my teacher, as the singing itself.

In my case, I learned that I tend to speak in very quick bursts - get a thought out at a rapid clip, followed by a brief pause. Actively trying to measure comes across as far more intelligent I think, and I have time to think through what I'll say next.

Really hearing how many pauses, contractions, etc. you include in your regular speech helps you improve dramatically