Place your foam roller on the floor and sit in front of it with your knees bent, feet flat on the ground. Carefully lie back and lift your hips slightly off the floor. Slowly roll your body over the roll, pushing your torso away from your feet, using your legs to guide you. You may feel your back crack as you roll back towards your feet. Proceed with caution, and immediately stop if you feel pain. (Skip this entirely if you have any pre-existing issues with your back).