To shoot accurately two things are imperative;
1) No other distractions and 2) clear sight picture
Distractions can be anything from activities around you, a pebble or fired case under one foot, the glare of sunlight, etc. Anything that robs you of your ability to focus on the target while viewing the sights relative to the target.
2) You must be able to see clearly.
When you start out you lack familiarity with the weapon and often with form, stance, best practices, etc. Use the tools that have been proven over years of design and research. Adopt a good stance, a good grip, and most importantly of all - GET COMFORTABLE. That is why not everyone uses the same exact stance or grip. Not everyone is good shooting offhand...good enough perhaps but not GOOD. We're all not gifted in the same ways so don't sweat it.
Working up an accurate load? Heck yeah. Its another rewarding aspect of the hobby.
Get a good rest and shoot sitting down at a shooter's station. Make your own sandbags from an old pair of jeans filled with coarse sand if no other is available. Don't make them floppy and don't make them rigid. You need more than one so you can stack or shift them around to a height and position that is solid and comfortable for you.
Experiment with different targets. I find a small aiming point improves my accuracy tremendously. I also prefer a small solid white dot but in a grey or shaded background perhaps ringed in thin black circles. For me the ability to silhouete my sights over the bullseye really helps. And I like to be able to see where I hit. Also set the target at a range where the size of the sights in relation to the bullseye is optimal for you. Don't concern yourself with what other's like at this point. Move it closer if need be. (presuming your range permits this)
Get rock solid yet relaxed. Focus on the sight picture while simultaneously squeezing the trigger. Do not anticipate the shot. When you do it correctly you will be surprised when the gun fires. As it discharges try your best to keep the gun on target even during recoil...don't look up to see how you did until you're back on target ready to shoot again. Either shoot again or then pause and study your results. In time you won't even pay notice to the recoil.
Once you've determined a loading that works for you, make a bunch up and go back to your offhand defensive shooting at silhouete targets and the like.
As you shoot you will know just what your load in your gun is capable of with you shooting under optimal settings. You can then strive to improve your performance under more difficult settings.
Then you'll be able to do what Clint Eastwood has been telling us for years!
( a man's gotta know his limitations)
TB