There's been a proliferation of small, sub-compact handguns on the market over the past decade or two. They're very useful when one's concealment options are limited. For example, I've carried Ruger LCP and LCP II handguns as a backup firearm in my pocket on many occasions. However, there's a drawback to all such small pistols. They're very difficult to operate accurately, fast and effectively, due to their diminutive size. They're also very fatiguing to use for extended practice sessions.
The same applies to slightly larger handguns, also falling into the sub-compact category. An incomplete list would include Glock's Model 42, 43 and 43X pistols; Springfield Armory's XD-S and Hellcat weapons; Kahr's MK and PM series; and firearms from several other manufacturers. I own a number of those listed here, and find them very useful for deep concealment. However, the same drawbacks apply to them as to even more diminutive weapons. Their small size makes them hard to shoot well.
In the not too distant past, one could simply trade in a handgun one didn't like to get one better suited to one's needs. However, in today's market, where quality handguns are as scarce as hens' teeth, that may not be possible. One might be forced to use what one has until such time as market conditions improve. If so, how can one adapt one's firearms to fit one's hand better, and make them more usable? There are several ways.
- Extended magazines and magazine sleeves. Many manufacturers, and some third-party producers, make longer magazines for compact pistols. See, for example, Springfield's extended magazines for its XD-S range, or ETS's aftermarket magazines for various handguns. Some manufacturers (both OEM and aftermarket) also offer magazine sleeves, which slide over extended magazines to provide a full-length grip for one's hand that's ergonomically matched to the firearm. A good example is the pairing of ETS's 9-round extended magazine for the Glock 42 with X-Grip's sleeve for that magazine, resulting in a full-length grip on the Glock 42 that makes handling it in rapid fire considerably easier. The longer grip may make concealment more difficult, but that's a penalty I'm willing to accept in return for greater controllability.
- Grip sleeves. These are made by various companies, of whom Hogue and Pachmayr are perhaps the best known. One pulls or rolls the sleeve onto and over the handgun grip, giving it a fatter, "stickier" shape that lends itself to a more secure grasp of the weapon. However, one has to be careful that the sleeve doesn't interfere with the operation of grip controls such as a magazine release or grip safety, and doesn't extend below the grip to interfere with changing magazines. Judicious trimming may be necessary.
- Skateboard tape or equivalent. There are several varieties of rough-surface tape available to use on stairs, skateboards, etc. When applied to the grip, perhaps on the front and rear or even all around it, they offer a firm grasping surface even to sweaty or wet hands, making control of the weapon much easier. However, some of them are so rough that they may take the skin off one's hands during extended shooting practice. I find I need only a small strip, front and rear. More than that, and I may bleed! There are also Talon grips, which add roughened stick-on panels to the grip area of many handguns. They're very useful, but more expensive than cutting your own out of a roll of skateboard tape.
- Hand strengthening exercises. In many cases, shooters simply aren't grasping the gun firmly enough, resulting in it moving in their hand during firing. It's a good idea to buy a hand exerciser and use it every day, aiding one's grasp on the firearm with what Massad Ayoob calls a "crush grip". I found it improved my shooting significantly over time. (Once your grip is stronger, increase the resistance level or move up to a stronger exerciser. It pays dividends. I started with this one, and I'm currently using this model. Both have worked well for me.)
- Shooting gloves. For extended training sessions, use shooting gloves. (I suggest not buying those intended for Airsoft - they tend to be cheap and flimsy. Rather, look for those intended for law enforcement use, which are usually stronger and better made.). They help absorb recoil and stop one's skin abrading against the firearm under the repeated stress of recoil. They won't help for concealed carry, but then, you aren't planning to shoot a lot under those circumstances, are you?
- Sub-caliber training weapons. Several compact .22LR handguns are available, similar to their larger-caliber compatriots, that can profitably be used to build up shooting skill without the heavier recoil experienced with a larger round. For example, Ruger's LCP II is available in a .22LR model., and Smith & Wesson's M&P 9 EZ pistol (or its companion .380 version) is almost identical in size and controls to that company's M&P 22 Compact model. This means buying another gun, of course, but does offer a way to practice with lower-cost ammo, perhaps during more frequent (and more extended) range sessions.
All those approaches, perhaps combining more than one of them, will help you master your smaller, harder-to-control handgun, and make it more effective in your hands.