Here are a few tips to maintain a perfect posture and avoid debilitating backaches.
While standing, hold your head up, chin in and look straight ahead. Keep your shoulders back, tuck your tummy in and keep your knees straight. Lean your chest forward slightly. If you're standing for a long time, rest one foot on a higher object such as a stool. Walk around as much as possible.
While sitting, keep your back against the backrest. Your knees should make a right angle and your feet should be flat on floor. Don't cross your legs. If you are at a computer, sit back and rest your arms on the chair's armrests while typing. Adjust your chair's height to maintain this posture. Walk around every 30 minutes to stay fit and relaxed.
While lifting objects, avoid anything more than a quarter of your body weight. Spread your feet apart and bend your knees, not your back. Hold the object close to your body. Straighten up at your knees as you lift. The power should come from your thighs and calves, not your back.
Finally, while sleeping use a pillow if you sleep on your side so your spine does not bend at the neck. A well-made, spine supporting mattress is a worthwile investment, especially since you spend a third of your life on it.