Despite the less perilous times we lived in when I was a child, my mom was quite worried about my safety -- perhaps because they have us great freedom. Her "go-to" tip was, "Kick 'me between the legs!" That was drilled into me. She also taught me that if someone was bullying or approaching me, to pretend I saw someone I knew and to "greet" them in the distance by waving or calling out.
It's interesting to me that I went on to a law enforcement career and, on the side, have taught many safety and survival courses for women and the general public. I have always incorporated the tip about pretending to see a friend in the area -- and to actually pretend to know the aggressor as well. Those are some of the more psychologically-focused tactics that are essential in addition to the physical aspect. All too often I think the psychological component is missing, and most certainly the strategic elements are.