Geinger!!!! Here are a couple drills that I really like for creating certain habits for success on the Geinger.

Number one is a backward roll down a cheese mat (air wedge pictured here). As you stand up, arms come down to the legs toward your twist direction. Chin should come toward that shoulder so you can see the floor early through the turn. Arms don’t reach back out forward until late. The goal is to create sight of the bar before reaching so you are specifically reaching for a target.
The second drill is based on the exact same concept, but it is done from a bouncy surface and only working the coordination of the arms to body, turn and reach.

The back roll version simulates the flip feeling a bit more and is therefor my favorite. But the other version is a great introduction.

Later twist allows for maximum height and rotation off the bar. Also allows you to specifically turn towards the bar and gives you an earlier visual of the bar to find the catch.

Hope this helps you and your athletes create their Best Darn Gymnastics!