Want to stop smoking? Don't light one up for the next 21 days. Want to sleep early? Start brushing your teeth at 9:52. Want healthy food? Think green for the next three weeks. On average, it takes people 21 days to start forming a habit. Jim Loehr and Tony Schwartz agree that by creating positive life-changing habits, you'll be more productive and engaged in whatever you're doing. Good habits will become second-nature - just like brushing your teeth.