I do keep aware of my surroundings and try to steer clear of trouble.
Avoidance should be the main tenant of ones self defense method, at least in my opinion. Trouble is best avoided in the first place. If someone goes around looking for trouble, or if they can't wait for trouble to find them, they don't think like I do thats for sure.
There are some good threads in T&T about awareness. Most of us aren't as aware as we like to think we are. It takes a conscious effort to stay alert and aware, in the face of the distractions of everyday life.