Let People Know When You Have to Draw
If you have to use your concealed carry pistol to protect yourself and others let the people around what is going on. A lot of folks will not have experience with pistols. They may think you are a bad guy if you don't. You should tell them right away what you are doing and why when you draw your weapon. You may not get a pat on the back when the incident is over, but you should get positive feedback from law enforcement.
It may be a good idea for you to practice the announcement that might have to make before you draw. Make it load enough so that people can hear. Make it understandable so that people will know what is going on. You will suddenly be in charge when you do this. You need to practice so you can get it right. You will only have one chance to do it right.