A simple spinal twist.
Sit with the legs stretched out in front. Pull back sitting bones so that you are sitting straight in lower back.
Place the right foot (with the right knee bent) on the far side of the left knee.
Now turn the whole upper body in the direction of the left knee and bring the hands to the floor.
Look as far around as you can and hold the position while breathing comfortably. The buttocks and straight leg remain fully on the floor.
Come back to centre, straighten both legs, pause, repeat to other side.
Repeat twice more to each side.