You need to know what your ambition is. Your goal. Like me, It's my lifelong dream to become a corporate lawyer, and i always imagine myself as one. I set goals, and all my goals will eventually lead me up to becoming a lawyer. You just have to know what you want to do in life and use it to motivate yourself. You need to look at how some things are more important than others, Like studies of course. Hopefully this should help.