I would highly suggest eating mostly fruits and veggies. Lots of salads. Then fruit for snacks. Make sure you're eating small portions instead of whatever is around to eat.

Then exercise! Running is amazing cardio for everyone. Jogging and walking too, depending on your level. Then you can tone up with sit ups and push ups.

Drinking lots of water will help you eat only when you're hungry and not just because you're bored or something.

Maybe drag in a friend for support. You can support each other and make sure you don't snack or skip exercising.

Good luck!

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kid, I wrote back,
all lovers betray.