Here is a link that may also help:
Also, there is one mistake that beginners normally make. Watch the trigger finger when the shot breaks. The normal reaction is to immediately release the trigger.
That is not doing a good "follow-through"
Your trigger finger should continue to pull the trigger even after the shot breaks. One thing that helps is not to release the trigger until after the firearm settles down.
To see how it affects the POI, do your dry fire routine. Snap your finger away from the trigger after the hammer falls, and watch the front sight move.
Get a movie camera and take pictures/videos of you shooting.
You will see your stance, hold, and the steps of shooting as you go through them.