I decided to participate in Cowboy Action Shooting (CAS) so learning the nuances of a SAA style cowboy gun was a necessity. It's been said that if us Boomers hadn't watched so many westerns, the SAA style of handgun would be but a memory. It is an archaic design, but many have learned to shoot it well. It does take practice.
Everybody's hand is slightly different, and I found you have to learn what works for you. If you pinky naturally slips below the grip, that's where it belongs. I suppose there are teachers or coaches that can help, but for most of us, we're on our own.
Practice on steel, it gives you the instant feedback required for motor skill memory. If the gun bites you, change your hold. If you can't get a comfortable hold, you may need to change the shape of the grip panel. But mostly, you have to practice, learn the skill. For me, it took a while. I sold a few guns because they just wouldn't shoot. I realize now it wasn't the arrow, it was the Indian.
Somewhere around the 5,000 to 10,000 round point it started to work for me. I still get bit occasionally, but for the most part, it works. CAS is about learning to shoot the equipment of the period, so the shooter has to adapt to the gun. In the end, this makes you a better shooter.
You also should bare in mind, the revolver was designed to shoot a Black Powder cartridge, the most powerful one of those was the 45 Colt, a 250 grain bullet going around 850 fps. If you had a 38 cal, the cartridge was a 38 Long Colt. At those levels, the SAA is manageable. Load your practice ammo to those standards, use a powder that mimics BP. IOW a powder that does most of it's burning before the muzzle.
I have a few Cowboy guns in 44 mag, and a longer barrel helps tame the beast. Some of the other calibers work OK with a shorter barrel. I have a 45 Colt and in a 4 5/8" barrel, it works OK. Same with 44-40.
In 357, anything close to a magnum load raps me in the knuckle. With 296 and 2400, you have a pretty hefty muzzle blast, tends to rocket the gun back just as the initial recoil is about done.
After you get proficient, you'll start to appreciate the old design, and you'll be able to pick up any SAA and shoot it, they are all basically the same. I regularly switch between "old" and new vaquero and Blackhawks in calibers from 38/357 to 45 Colt with different hammers, and have tried a 75 Remington in a match with no prior trigger time, and it ran well for me, never really noticed the difference. And it had a bobbed hammer to boot.
When I think of shooting a SAA, the clip from the movie Quigley down under comes to mind, and the the classic line, "I said I never had much use for one. (A Colt revolver) I never said I didn't know how to use it." ~ Quigley " The revolvers in that scene were 44 caliber 1860 Army Colts, the SAA was a later variant of the same basic shape, introduced in 1873 as a cartridge gun. Rooster in True Grit carried a pair of navy sixes, 36 caliber.
Shooting a SAA is the closest most of us will ever get to travelling back in time, unless you ride a horse. Enjoy the trip.
I ended up buying a progressive press to keep up with my demand for ammo. In addition I did learn how to shoot with my left hand as well. After 50 plus years of shooting right, that was a challenge. I'm OK, just not too fast. I mention this as the new vaquero works best in my left hand. And the gun of choice is a 5 1/2" barreled NV with a Montado hammer. I prefer the longer barrel in the left, as it's a bit easier to reholster. My left hand doesn't work all that well for some tasks. And dropping a handgun at a meet, not good.