Find the position that works for you. Then as said above PRACTICE. Quite a few years back some other ranchers and I set up a steel silhouette range. The targets were from 200 meters to 500 meters . This is all off hand shooting. When we started it was a joke. None of us could hit the steel critters without a rest. As time went on we all started getting pretty close. Closer each week that we would shoot. After a few months we started hitting them more and more. If we took the winter off it would start all over. To improve my shooting I would spend a couple days a week with my 22 shooting different size targets. I would off hand shoot a couple boxes of 22 shells paying attention to doing things the same each time. It works and I know of nothing else that does. All that said, I never shoot off hand if there is any other option. At game animals that is.