Do some daily cardio such as running/jogging, cycling and rowing. As you get more advanced, going to the gym to work with free weights will help you tone your muscles, which will help you lose additional fat. Lifting weights will not get you big and brawny as most girls think so don't worry about the fear of looking like a bodybuilder! Complement your exercise with a good diet incorporating lean meats and veggies whilst cutting down on junk foods and sugars. In a nutshell, to lose weight, you have to burn more calories than you consume.