What should you do after defending yourself with a firearm? Two things ...
Why brandishing, shooting to wound, and warning shots are BAD ideas
For every bit of good advice out there about self defense, there are at least 10 pieces of bad advice.
Some of the very worst advice is about how to avoid the legal fallout of self defense by using a firearm in a non-lethal way, such as brandishing, shooting to wound rather than to kill, and firing one or more warning shots to scare off an attacker.
On the surface, these ideas seem to make sense. After all, why kill someone if you can end a confrontation in some other way? The problem is that besides being in many cases tactically unwise, the idea of introducing a firearm into a situation before you're actually in fear of death or great bodily harm can lead to serious legal troubles.
Perhaps the best explanation for this comes from Ken Hanson's book The Ohio Guide to Firearm Laws, Fourth Edition, pages 76-77. While written for Ohio gun owners, you should consider taking Ken's advice to heart no matter where you live.
Prosecutors have another term for warning shots: attempted felonious assault, improper discharge of a firearm etc. Shooting someone in the leg rather than center mass is similarly misguided and will not evade serious felony charges. Similarly, pulling out a gun just to "defuse the situation" is a legal non-starter. Do not be tempted to do this. If the gun comes out of the holster, the gun owner had better be justified in immediately employing it fully. There is no such thing as a warning shot or shooting to wound. This will be construed as a miss, bad marksmanship and perhaps even attempted murder.
This author understands the theory that the presence of a firearm might eliminate a confrontation. However, the opposite is equally true. For illustration purposes, assume the following: Someone was rudely and dangerously cutoff on a street, the horn blast that logically followed developed into the "cutter" getting out of the car to go yell at the "cuttee." The "cutter" does not display anything other than bare hands. Unfortunately, "cuttee" then displayed his handgun in the honest belief that it would avert/end the confrontation. Bad move.
First, no threat of imminent serious physical harm or death had been made, thus the person who took out the handgun did not have any legal justification for using lethal force. Second, the "cuttee" has escalated the situation: Within his own car, without any threat of serious physical harm or death, he removed a handgun from a holster. This action clearly, in this circumstance, could be construed as a threat. Would the "cutter" now be justified in drawing a handgun of their own and shooting the "cuttee," assuming it wouldn't violate a duty to retreat? This scenario will always present more questions than answers, and the gun owner is going to be playing against long odds if he brandishes a firearm in a non-lethal situation.
Removing a handgun from a holster, or even possibly just uncovering and indicating the presence of a handgun, can be considered a hostile act and will be considered a criminal act. As the old saying goes, an armed society is a polite society, and people do not need to be waving guns around to accomplish this. IF YOU ARE GOING TO TAKE YOUR HANDGUN OUT OF A HOLSTER, YOU HAD BETTER BE LEGALLY JUSTIFIED IN USING IT IMMEDIATELY.
Readers, students and the general public never like this answer, but I assure you it is an accurate answer under Ohio law and has withstood the test of time and appellate cases. Any deliberate action on your part that introduces lethal force into the encounter in a manner that makes the other person aware of the lethal force, IS THE USE OF LETHAL FORCE. If you make reference to lethal force, show lethal force, hold lethal force in your hand etc., those actions are simply an alternative use of lethal force, short of pulling the trigger. If you are in a non-lethal encounter, and have used lethal force, even in this round-about, alternate way, you have escalated the encounter and will have difficulties proving your self-defense case.
In short, don't draw your firearm until you honestly believe you are in immediate danger of death or great bodily harm. And if that is truly your belief, you don't have the leisure of brandishing, shooting to wound, or firing a warning shot.
At that crucial moment, you should do what you've been trained to do: stop the attack by shooting your attacker center mass until the danger is gone.
Then, if you end up in a courtroom, you can honestly and with conviction look the jury in the eyes and say, "I feared for my life. I had no choice."