I think there is another level to be considered even before you get to the being aware of what is around you phase.
I start by choosing where I live and what i do for a living. Detroit and drug dealer were not on my list.
Given that I live where I do and earn my keep the way I do, there are places that I don't go if I can help it. There are times that I am not running around away from home if possible. There are people i stay away from whenever I can.
(Like someone's grandmother said, "Ain't nothin' good happens after midnight.")
When those conditions cannot be met, I start paying a lot more attention. I am not walking around a shopping mall in Longview like I was on a patrol overseas.