Any tips on intentionally lucid dreaming?

(Inspired in part by http://www.fluther.com/disc/60804/whats-the-freakiestscariest-thing-you-thought-youve-seen/)

I know there have been lucid dreaming questions before, but they were fairly general. I have experienced dream consciousness tens of times, but only have I been “in control” of parts of my dream a few times. Usually, if I am aware that I am dreaming, I just watch what is happening.

Does anyone have first-hand tips on gaining control of a dream, gaining consciousness, etc.?