The simplest way to burn fat off your entire body is to walk it off, literally. Walking 30mins to an hour everyday really burns the fat. If you desire a lower impact solution and have the money, then get an eliptical machine. They are proven to work just as well.
Exercise! Exercise! Exercise!. That is the mantra to lose fat. Do lot of aerobic exercises like swimming, jogging etc. You can also do sit-ups and squats. Watch you daily calorie and fat intake. You need to burn enough calorie each day by physical activity.