I was learning how to shot pistol many years and still make mistakes. My mistakes are in two groups. 1-one i can correct, 2 - i can't correct. Example for 1 - I feel tired and i decide to drive and shoot. Example for 2 - i don't see well beyond 15 yards.
I took me about year to understand that I have t use my targets. So i don't buy targets, I print them home. Use common copy paper from Walmart, laser monochrome printer. I was changing template many times, my finals are:
If you want to try them, I will sent them as jpg to your email, i can't use PM - low number of posts
They are clean, monochromatic. In many situations variety of colors distracting you, and also variety of shapes, figures.
You can place them easily on the same level your eyes are.
Targets are small, shoot 5 rounds and change the paper. Stop use target big as table cloth. When you make 50 wholes nobody knows what is going on.
If you shoot off paper 8.5x11 for distance 7 yards is time to use support for
your hands. The best is Core Pacific 12 inch Step Stool Black with White Dots from Walmart, and some towels, cushions. To make one level for your eyes, hands with pistol supported by steps-tool, and bullseye. Then you start to notice what is going on with your palms.
Use diagnostic pistol shooting target as advice what to correct during shooting
Control your eyes. Some people close eyes as reaction for shoot. Right-handed person suppose to aim with right eye. My better hand is the right one, but sometimes I notice that I use left eye to aim.
The list of shooting problems and issues is much longer. I didn't have any instructor. I bought firearms, which I don't use because I really don't like them. Nobody is perfect.