Eating 5-6 smaller meals a day, whenever possible. Cut the overly processed carbs and eat whole grains/veggies. Cut out the sugar...including sugary sodas (sorry about that...but true). Cut back some of the fats and drink plenty of water. Be sure you eat breakfast! As a teen I usually forgot to do this and paid for it later on during the school day. Also do not fall into the trap of not eating enough calories to lose fat. Then your body will slow it's metabolism into "starvation mode" to conserve its fat stores. Nor think that using fatloss pills will do the trick instead. My teenage daughter had a friend who did this with nearly disasterous results. She was lucky that my daughter talked her into getting some help and pulled out of it.

A good exercise program to build muscle tone and cardio....considering some the routines I have seen (all that jumping and lifting others up).....you will need it.

Lifting weights will keep your metabolism up longer to burn the bodyfat as energy. It forces your body to work harder to do this. Most women/girls need to gain upper body strength as well as in the lower too. Lifting will not turn you into a female "Arnold".....women do not have the hormones to do this...however, it get you looking more fit. Get your curves and keep them too. By the way, do not use the scales as a measure of pounds lost every day. This can be frustrating if you do this as the body gains and loses a pound or two depending on a variety of reasons. Your wardrobe is a better indicator of the changes.

Do some kind of strength lifting three days a week for at least a hour. Add cardio on the nonlifting days or right after the lifting.

Finally it is patience, patience, patience and time. Stay determined and motivated. Dont expect immediate results in the first few weeks, but you should see some significant results in two months.