A coaching tool I like to use is this handgun correction chart.
That is definitely not to say that the sights do not need to be adjusted. That can happen, but usually if your shot groups are small and in one area is when you want to adjust the sights to move that small group to the center.
If your shot groups are wide, try to play back each shot in your head thinking about the possibility you may have pushed, pulled or jerked a tad more than you should have.
Use this chart to analyze each shot right after you took it. Having a spotting scope to help see the holes is often necessary at anything but real close ranges.
