I would say this is mostly CORE, shoulders, lower back intensive.
Exercises that would increase mobility and strength include:
Yoga - stretching flexibility core stabilization
Core work - planks, weighted crunches, leg lifts, hanging leg raises
Military presses lateral raises - work your delts and traps for stabilization to hold that position.
Getting into position is probably the hardest part of this. You can start by standing a little less than a body length away from a wall. Get in the starting position with your head tilted down and your hands palm down on the floor. I believe you start sitting. Place your hands directly under you and practice holding yourself up, pushing up off the ground, hold and repeat.
Get a chair and place it behind you, or use the wall as mentioned previously. With your hands in the same position as the starting position, kick your legs up to the chair or a low point on top of the wall, hold, repeat. This should be like the half way point, maybe a little less than half way point.
I think your main goals for this is to get your core in shape. If those core exercises are too extreme, maybe you could try pelvic tilts, or other core activating exercises so you know what it really feels like. This is probably just a start. Good luck!