Report what you know, or what you have seen -- dont base your report on speculation. That only creates panic and might even assist the enemy, who will definitely take advantage of the confusion. Another drawback of false reporting is that if there are too many hoaxes, the police often start taking things lightly and develop a disbelieving attitude.
In case of an emergency, know where to go
Make a note of the closest security officer in your area and the closest police post. In case of an emergency, you should know where to go and the fastest way to get help.
Protect yourself
Last of all, learn a form of self-defense. You don't need to be a black belt -- even a few tricks can get you out of a pickle, and may save your life in case of an emergency.
Also see: Citizens rally for Mumbai