In aiming, you'll find it important to focus primarily on sight alignment. Sight picture clarity will help your shot more than a little target fuzziness will hurt it. That way, you'll be concentrating intently on sight picture and will not be disturbed by report and recoil. If you're too acutely aware of these, you may flinch, and pistols are quite unforgiving. I'm sure I fired twenty-five shots to hit the paper ten times.
Dependable equipment is essential to good pistol shooting.
At the very least, your lock should be quick and strong, and a good sparker in the flintlock variety. Flintlocks will benefit from a good flash-hole liner. A flash hole that's too small can be carefully opened up with the next-larger drill. And while a flash hole that sits too low can't be raised, the same effect can be achieved by grinding away a little bit from the bottom of the pan. If you make your pistol from scratch or a kit, you might place your rear sight as far back as the breech plug tang to increase your sight radius.