In some reading I did on lucid dreaming pertaining to flight I came across this bit of advice. "Try to imagine you have a force coming out of your feet or your body and use that to propel you forward."
Let me just say...holy cow it WORKS. Talk about the best dream EVER. I'm having a hard time cornering or even changing directions quickly but the sheer fact of being able to TAKE OFF and KEEP GOING is pretty frakking amazing.