Take the position with your legs spread at shoulder width. Grab the flat side of the BOSU ball to face you. Stretch your hands forward while holding the BOSU.
From the starting position with hands stretched forward rotate the BOSU alternatively to each side. The movement resembles moving a steering wheel. Keep your elbows slightly bent and pull shoulders and shoulder blades backward and toward each other and down throughout the movement. Do the required number of repetitions equally to both sides. Inhale in the starting position and exhale when you are rotating the BOSU.
Pay attention to your body posture, fixing your body core and keeping your pelvis in a neutral position and avoiding over-bending your spine.
Keep your shoulders in a neutral position and do not shrug them forward to eliminate excessive engagement of the upper trapezius muscles.
If possible, exercise in front of a mirror to watch and eliminate lifting your shoulders and excessively engaging the upper trapezius muscles.