1. Move... Very simple your body needs it thrives off it. Most of us sit down far far too much.
2. Eat well... This one is number two for many it's perceived as number one priority but really your diet is lead by how much you move and what your nutritional demands are.
3. Think positive ... Easier said than done. And perhaps more important than my number 1 and 2 for some people. Let's call this a floating priority, some days it's 3 others it's number 1.