4) Use Your Carry Gun
This sort of goes without saying. If you carry a J-frame but practice with a 1911, well, the reality disconnect is obvious. You'll have to give up the performance that you're used to at first, but you might be surprised at how well some of those little guns shoot (particularly the J-frame.) The ability to hit A-zones at 15 yards will be of small comfort if you can't defend yourself at two.
5) Move and Seek Cover
Don't just stand there! Either get to cover or move laterally - which is the single most effective thing you can do to avoid getting shot yourself. Even aggress on the target - that is, move towards it. In a multiple threat situation at close quarters, moving towards one threat may be necessary to accomplish your overall goal of triumphing over them all. But make every shot coincident with a movement of some sort. After a little of this, standing still and shooting will seem uncomfortable.
6) Draw From the Holster
This is another obvious one, but don't get in the habit of firing from a ready position or from the bench. In real life, the first shot from the holster is the most important one, and firing from the holster is the most likely scenario for you as the defender - so re-holster after every string and draw to begin each one. A range that does not permit this (shooting from the draw) is a range you may need to find a replacement for. At the very least, practice holstering and firing with a dry gun at home - a lot. Oh - and do this from your normal concealment garments. No cheating.
7) Staple an Old T-Shirt Over the Target
Get used to shooting something that looks like the violent criminal you may have to shoot for real. You don't need to dress the target in an old garment, just staple one to whatever target you use. And maybe use a copy machine to blow up a face picture of Osama Bin Laden or Adolph Hitler to life size, run off a bunch of copies, and staple them in place over the t-shirts.
8) Shoot at Multiple Targets
Do so at close range. Attacks happen fast, up-close, and are increasingly perpetrated by multiple assailants. So set up a few targets in random positions (positions that are safe for your range), and get used to the gross body movements that are necessary to get fast hits. This experience is not at all like the small hip rotations that are used for multiple target engagements at longer ranges. It's a whole new set of movement, balance and body mechanics skills to be mastered. It's much more physical than typical target shooting.
9) Hit the Target
Since your attack is likely to happen at touching distance, get used to integrating empty hands techniques into your shooting repertoire. The most common technique is to strike the target - as hard as you are able or the target will stand - with your hands or feet twice or thrice prior to executing a fast draw and assessment. You thought that carrying a gun got you an excuse slip for not learning empty hands techniques? The facts belie that myth. You'll have to deal with many, if not most, attacks with empty hands just to get the moment of time necessary to access your gun.
10) Practice Dummy Gun Scenarios
Anyone can learn to shoot at paper targets, even up to the limit of realism - as per the above - that the range allows. The next step - and the one that will determine your street results - is to practice fighting against live, thinking human beings. You don't need a range or even a gun for this - just a dummy gun and dummy knife or two. Practice with a partner, one person being the bad guy and one person being him/herself. Simulate scenarios that are realistic for your lifestyle and location. Learn to be aware, to verbalize, to de-escalate, to find cover, to properly handle the aftermath and to fight in full living 4D color. If you have honed your marksmanship and hitting ability on the range, then you can assume you will hit when your dummy gun fires. Here's your opportunity to practice all the much more complicated aspects of survival gun fighting. This costs nothing and can be done anywhere, anytime.