There are many ways to improve your shooting that don't always require sending lead down-range. It only takes a few minutes a day to practice drawing, aiming, and dry-firing you concealed firearm of choice... just make sure you check three times that the gun is empty before practicing. You can also get your physical condition in better shape, but one thing I've found that helps folks of all ages and all conditions is to get their grip and trigger finger in better shape.
There are a lot of good products on the market to improve your grip and finger strength. We had some of those old "spring-clamp" style exercisers for years, but the resistance pressure was hard for the wife to use and it didn't work each finger individually. I ran across the Gripmaster Hand Exercisers several years ago at Dick's Sporting Goods. I bought a couple of their red seven-pound models and eventually picked up a couple of their black nine-pound models. I use them daily doing 50 or 100 reps in different variations a couple of times a day, usually during my almost hour drive to work, to improve my grip and trigger finger strength and stamina.
They will help improve shooting performance for just about anyone... they can improve my daughter's varsity tennis grip... and my wife's grip in general after having wrist surgery due to a RSI a few years ago from twenty years in her younger days spent as a majorette and baton twirling instructor. (Yes, while everyone else was chasing the cheerleaders and prom queens, I married the lead majorette... bathing suits with sequins... what else can I say.) After recommending them to a sixty-eight year-old gal, taking my NRA Basic Pistol/CCW course, who had trouble with hand strength and dexterity... she reported great success in shooting and daily tasks after using them for just a few weeks.
ProHands makes Gripmasters in three, five, seven, and nine-pound resistances in addition to two other lines of hand exercisers. They are easy to work into your daily routine and you don't have to set aside a specific time to simply work out your grip and fingers. I use one while driving in the truck or car (carefully), we also use them while riding the Schwinn AirDyne Evolution Comp, and have a set on the end table near my favorite chair.
The next time you're looking to improve your grip or trigger finger strength and conditioning, rather than sitting in front of the flat-screen and reaching for another potato chip... reach for your Gripmaster Hand Exerciser by Prohands.
Note: I realize there are dozens of sexual innuendos possible with this review... folks are welcome to chuckle to themselves, but please leave them out of the comments.