If you do find yourself in a dangerous situation where you are being threatened, try and diffuse it. That is, try not to make the situation worse by getting angry or trying to fight. The best defence is to remove yourself completely from the situation. Calmly walk away if you can, but if you feel you have to run away, then that's what you should do,as fast as you can. If all else fails and physical force is your only choice, then you must fight back.