You sort of have to be always aware, even when you're not thinking of shooting. That's when the best stuff happens.
Be aware of every square millimeter of your frame.
It's a lot easier to take pictures if you always have the camera with you.
Always wait for the trigger. The trigger is the final part of the puzzle, the reason you want to shoot.
You must be open to what otherwise may seem to be a detriment to your 'plans'.
You have to let the past successes go, or you'll never be able to see anew.