Hard To Break Habit

The habit I find the hardest to deal with or to break is the facebook habit...well more like addiction...I have this habit of always..literally always getting on facebook whenever I sit down at a computer...its like an automatic reaction...and this habit or addiction whatever keeps me from what I need to be doing...like schoolwork...writing papers etc. how to break this habit...i have no idea. maybe its called self control..i dont know but I do know that I have got to break it or i will never get anything done. haha but seriously I really need to lay off the facebook addiction.