Always lock your home door when you go outside.
This is an obvious safeguard. Build a consistent, fail-safe routine (ex. put the keys in your left pocket if and only if you have just locked the door- this provides later reassurance when in your car or down the street).
Always lock your car doors as soon as you and your passengers are inside.
Make it harder for weird strangers to access your car while parked or in slow traffic. Make it harder for children to open a car door, accidentally or not.
Always put a password on every personal phone or computer.
Not having a password is convenient. But the personal risk is too high in the case of a stolen or misplaced device, especially because they remain logged into your email and other accounts. Even a simple password like "ComputersAreCool" is much better than nothing while being easy to type and remember.
Always log out or suspend your computer before you move away.
Avoid leaving yourself carelessly vulnerable, especially in an office setting. In the harsh real world, ill-intentioned co-workers (even those who seemed to be on good terms with you) will sometimes bear a grudge and try to frame you for criminal actions (through your logged-in computer) and jeopardize the rest of your life.
Always maintain distance with strangers during a conflict.
People can be unpredictably dangerous, especially during emotional periods of social tension. Don't give them the opportunity to hit you.