Sit upright in a firm chair with your feet hip width apart.
Move forward slightly, so that you are not leaning on the back of the chair.
Raise one of your arms, and reach slightly up and diagonally away to the side.
As you reach up, lean your weight onto that side of your pelvis.
As you do this, lift the opposite side of your pelvis off the chair.
Aim to keep your body upright and your shoulders level, rather than leaning over.
