You should first and foremost be passionate about what you do. If you hate it then you're not going to get very far. The rest comes with experience, testing and practice.
I can say I enjoy loving my work more than my rest time, eating time, or partying time, even though it's pretty stressful, and requires most of my day time. It's pretty much all I care for nowadays. I don't think I could manage to work an easy 8th hour job that I wouldn't be addicted to.