At first We all have to make our mind in the sector of study. It does not mean to study 11-12 hour a day. Only studying 3-4 hours is enough. Always sit in a good posture. Whenever you think today I want to read very long day you all need to do is sit study at that time because your motivation level will be 100%. If you start doing late your motivation level goes on decreasing and a phase will come when you will always think to study at tomorrow's day. Do your best