Once you've obtained a safe firearm to practice with, have a seat in your dining room chair, or similar sturdy seat. Your gun should be in your holster.
If you're right-handed, as you're seated in the chair, draw your handgun from your holster, and without crossing any part of your body with the muzzle of the gun, bring the gun over to the left side of your chest. Take your off hand and bring it over to your forearm, as if you were folding your arms in front of you. Now cant the firearm slightly away from your body so the slide doesn't get caught on any of your clothing. Once you do this, tighten up all of the muscles in your arm. Tightening the muscles in your arm will help you absorb the recoil from the gun. You are now ready to fire.
If you're a left-handed shooter, your gun is obviously on your left side. If an attack were coming from the passenger side of the vehicle, you would perform the drill the same way by bringing the gun over to your right chest area. If the attack is coming from the driver's side, you'll simply draw your firearm from the holster, index your elbow into your left side, and then lean hard to your right so that you're over far enough to place a shot into your assailant. Remember to tighten up the muscles in your entire arm to help you absorb the recoil of the gun, which will help you control the gun during rapid firing.
If you're a right-handed shooter you'll perform this same drill if the attack is coming from the passenger side of the vehicle. Draw your firearm and index your elbow into your right side. As you're doing this, lean hard to your left, into the door, so you can place a shot into the bad guy.
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