Eat a lot and exercise a lot or eat a little and exercise a little.
Cut out or reduce refined carbohydrates and sugars. Ice cream, cakes, cookies, donuts, pastas and breads are all refined and cause body inflammation.
Sleep more. People who sleep less gain more.
Get off your chair and move.
Do fun activities. If you go to the gym and hate the idea of it, you will not stick with it. Find an activity you will stick with. Try hiking, dancing or walking around the block. We like scenery, it makes exercise more enjoyable.