Be prepared.

     It's a lot more than the Boy Scout motto.  Being prepared is all about shifting the odds from you being a victim to being a survivor.  This applies to everything in life.  Here's one example: anyone who lives on the East Coast, especially in the Southern states, knows to be prepared for hurricanes.  You put at least a week's worth of food in the pantry and fill the tub with water before the storm hits.  You keep batteries and candles and an extra propane tank for the grill handy.  And lots of other crap.  Because we all know that you could have to ride a storm and the after-effects out for days, perhaps even weeks.  However, taking steps to ensure your survival should go further than just guarding against acts of nature.
     People usually live their lives violence-free.  This is how it is supposed to be, but not always how it works.  Locally, we had a small, family-owned convenience store get robbed.  All three of the men working that night were murdered by the thieves.  They handed over the money promptly and without resistance, remained calm in the face of danger, and did everything else they could to comply with the criminals.  And they got shot to death for their efforts.  Here's a link to cut-and-paste for those of you reading this from outside of North Carolina:
     http://www.witn.com/home/headlines/Search_For_Killers_Continues_146037285.html
     The murderers have been caught and I am confident that they will spend a great deal of time in jail for their crimes.  That does fuck-all for the people that had their store robbed and family members murdered.  The unhappy truth of the matter is this: sometimes, no matter what you do to avoid it, violence will happen to you and yours.  Some people can't be talked out of it.  It is what they want, and they will have their way no matter what you want.  If anyone had survived the 9/11 hijackings they could tell you the same thing.  The best thing you can do is to be prepared.  This doesn't necessarily mean toting a gun with you everywhere, although that is one hell of a deterrent.  A knife is another.  Learning to be environmentally aware is a really important skill to develop.  Training is another thing to consider, with that gun or knife, or in some kind of self-defense art.  The importance of this cannot be understated.  It prepares you for the mindset you need in violent (pr otherwise dangerous) situations.  Many people are unprepared for this, untrained for this, and so the aggressor has a tremendous advantage.
     I can't say for certain that any of these things could have saved the three men mentioned above.  All I can say is that it would definitely have increased the odds of their survival.  And that is the best you can do.