Here is a good starter Blind Change Drill!
The back extension roll provides the momentum of the rise towards the handstand and simulates the giant. The block set up allows for athletes to turn either direction based on their twisting/pirouetting direction that you have settled on for that athlete.
The back block is a stopper so as they try to figure out the turn, they have a backstop that helps them feel their turn was incomplete going past vertical. Also this allows them to correct themselves and find the correct finish position as well.

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