Do you have target grips on your pistol? Sometimes those can help because they tend to fix your hand in one position. I always put the gun into my hand the exact same way so that I have consistency. IMHO, consistency is a key to improvement. If you break down the various steps into pieces and do them all the same way each time, you can then experiment with just changing one thing at a time and see how it affects your score.
Another thought is to spend a practice session concentrating on just one thing, e.g., a smooth trigger pull. Or how you breathe, or how tightly you grip the gun, etc.
That bullseyepistol site I linked above has a lot of really good stuff on it.