Hi Manon!
I also had a hard time finding a stable position when wrapping the arm.
The first thing I found to be important is to make the footlocks even (as Brandon said) or to wrap the left leg a bit higher. Then you have some space to move the right leg underneath you to find the stable position. The best position for me is when the right leg is underneath the left thigh, almost like you’re sitting on it. Also, I had to adjust the pole on my left hip to slide from my waist to the side of my hip. Actually, the sliding of the pole happens by itself when you move the right leg beneath the left thigh (because that pole is attached to your right leg).
