IITs are premier institutes and dream of many students.

In order to fulfill your aim you should be dedicated and self motivated.

If you want to crack your exam you should focus on quality of time rather on quantity. You can give 8 hours to your studies with full concentration.  

You should make your time table according to your comfort. So, that you can follow it easily. Set your time table according to your strength and weakness. 

To crack IIT-JEE you can refer below points-

1- You should refer NCERT books for your preparation. Make sure your basics are clear. Don't use much reference books. You can use good recommended books for your preparation.
2- You can use previous year papers to understand the exam pattern and level of questions.
3- You can solve as many as MCQs for your practice and to build up speed and accuracy. You should solve short-answer questions, subjective-type problems and questions based on assertion reasoning to develop deep understanding of the subject.
4-Focus on the Important topics for JEE Advanced which carries more weightage in the exam. 

Good Luck!!