Put something heavy on a large piece of cloth and wrap it up.
2. Slightly bend your knees and hinge at your hips until your back is at a 45 degree angle (If you can go lower, no problem but 45 degree in the minimum).
3. Flex your abdominal muscles, keep your back straight and raise your arms by flexing your upper back muscles until your arms are parallel to the ground.
4. Hold the contraction for a moment and slowly lower your arms back to the starting position.