Sit up straight in front of a table.
Place your forearms on the table leaning your body forwards.
Ensure your back remains straight with your weight through your seat bones.
From a neutral position with your head, pull your head backwards so that your chin tucks in.
Keeping this position, turn your head gently one way and then the other.
Ensure only your head moves and your neck remains still.
This is a small, subtle movement.