Balancing is required in so many asanas & combination of the physicality & concentration. I had to learn, adapt & practice to hold balance. For me, I had to raise my toes in order to feel where I felt the most unstable in the sole of the feet & then try to ‘grab or claw’ the floor with my toes giving it some tension & stabilizing my balance. Softening knees helps as well so just experiment what gives more stability to you. With practice my ankles became stronger, helping with keeping balance with movements & not just in static poses.
