It pays to pay attention. Awareness 101

The prudent course of action while in a public area is to keep your head up and your eyes and ears open. Having your head "on a swivel", like a radar constantly scanning the area, is a smart way (and the only way) to maintain situational awareness. In order to truly maintain a higher degree of awareness, you need to avoid cell phone texting while walking in public areas, especially at night. You need to avoid the lazy habit of keeping your hands in your pockets when walking down the street. You need to be alert, aware and relaxed.

I am not advocating that you should always be turning 360 degrees and watching every movement on the street. You do not need to be paranoid or fearful of your surrounding environment. The best security specialists are relaxed yet alert. They are ready to roll in a split second yet they seem to be at peace with themselves and their surroundings. They exude confidence even if they are experiencing fear or doubt. Confidence and awareness are key elements to urban survival.

The criminals and gangs want to attack the weakest sheep in the flock. When you walk with confidence and project a relaxed yet alert/aware self image, the criminal or gang will most likely avoid you in favor of easier pickings. They want the weak sheep, not the self confident sheepdog.

You can practice this the next time (and every time) you are out and about in public, be it at the mall, in a parking lot etc...

Stand straight, shoulders back, head up and eyes looking level ahead. Your hands are out and not in your pockets. You are scanning your immediate environment by simply looking at people and objects and recording what you are seeing. Treat it as a game and you won't feel so awkward when your eyes briefly scan across the eyes of a stranger. You are not "staring them down" since that is overly aggressive and can create unnecessary tension.
Rather, you are simply swiping your eyes across their line of sight, so they notice that you are aware of their presence. The glance should last no longer than half a second and the glance should be directly across the eyes and continuing on sideways, never down. A glance followed with your eyes looking down projects weakness.

Pay attention to the details. Let your brain process what you see. When your brain or body tells you to be on alert, listen to that message and act on it. To disregard that message, no matter how strange or frivolous it may seem, is to ignore a million years of animal survival instinct drilled into our DNA.

Always expect the unexpected.