Yes, cardio burns calories. But people often neglect strength training, which can help you lose fat for the long-term. Eric recommends lifting weights three times a week starting out. Weightlifting will help you build lean muscle, which burns more calories at rest. It will also change your body composition so you'll look more toned and defined.
And don't be afraid to lift heavy; it will help you lose fat, not get bulky. If you're just getting started, check out this four-week strength training program.