How to reduce facebook addiction?

plz plz suggest some ideas fr this. m too much addicted to fb . i sit fr several hours on fb nd i can't spend even a single day without it. all d tym i sit on my pc nd i tried so much but still i can't control. i deactivated my account so many tymes but then i reactivate it again. plzzz help it is affecting my studies . i want to get rid of it