Your most immediate and best option is to combine aerobic exercise and exercise involving lifting weights, as you will not only burn body fat but tone your muscles as well, positively changing your hip to waist ratio, and working quickly towards a healthier body in ever aspect. As you burn belly fat, you'll burn fat where it doesn't need to be elsewhere, too!
Cut back on calories. The most important part of losing weight is not working out until you collapse — it's your diet. If you burn 500 to 750 more calories than what you eat every day, you will lose 1–2 pounds every week (any more than that is considered unsafe weight loss). There are tons of little changes you can make to cut calories from your diet, from replacing high-calorie dressings with vinaigrette and asking for all dressings/sauces served on the side, eating at the table instead of in front of the tv, skipping cheese and other fatty additions to your salads and meals, using smaller plates, leave off the whipped cream on your coffee drink, and on and on.