The first thing that anyone needs to realize in their quest to lose weight quickly and to burn fat is that you need to burn fat. Burning fat requires you to use more calories each day than you consume. If you wind up eating more calories than you burn, your body stores these additional calories as body fat.
To keep your body from building more body fat you need to reduced the amount of calories you consume each day or increase your increase your daily exercises level. A combination of the two will help you the most.
Basically all this means is that the more body weight that you want to lose quickly, the more calories you have to burn and the fewer calories you need to eat. There is one key thing you can quickly do in your question to lose weight.
Boost your metabolism by exercising more. Exercise has been proven to increase your bodies metabolism. The exercise you do, the faster your metabolism works and the fast it will burn calories. This alone will help you to lose weight.
Exercise speeds up your metabolism. The more exercise you can add to your day the faster your metabolism will get. You have to be careful though. Don't start a extremely intense exercise regime right away hoping to lose weight quickly. Start out with a reasonable amount and work yourself up to the next level. Keep pushing your limits, but be safe and don't do something that could hurt your overall health.