Lay on your back with bent knees and feet flat on the ground and place your hands on opposite shoulders.
Keeping your heels on the ground and your toes flat to the ground, engage your abdominal muscles and gently lift your head first, followed by your shoulder blades, coming into a full-sit up position. If this is too hard, just lift the torso as high as you can.
Hold the position for a second, and with control, come slowly back down to lying on your back.