*. Keep your radio at a moderate decibel level when driving in residential areas and cities, and never pass out or start fidgeting with your phone at every traffic light. Carjackers & muggers rely on the aspect of shock, thus if you stay watchful of what's happening beyond your vehicle, shoddy guys would not have an opportunity to creep up on you.
*. Properly lock your car: You wouldn't leave your front door unlocked and your windows open at home, so stay in the habit of locking your vehicle in the same way. Keep doors locked when you're driving, and windows closed. In scenarios when individuals approach you for change or for directions, make sure that it is not a ploy to sidetrack you. Crack the window a little instead of opening it all the way if you make your mind up to speak with a stranger.
*. Don't presume that an unmarked vehicle with flashing lights is a police officer: If you believe that the car that wishes you to pull over is not driven by a law enforcement officer, then carry on driving until you find a well lit area with people and after that stop . Stepping out of the vehicle in such a scenario is also not suggested, and do not refrain from asking for the person's ID if you have any doubt.