1. Start by eating a healthier diet, that includes eating more fruits and vegetables. Also drinking more water and milk.
2. Buy a workout outfit. (You can find them almost anywhere such as Dick's, Target, Walmart.) Get some nice running shoes to go with it.
3. Start taking a walk(or run) everyday to every other day.
4. Instead of taking a walk(or run) you can do different exercises (such as push-ups, sit-ups, toe-touches, and many more.
5.Take vitamins every night or morning.
That's about it. Sorry that it was so short.