Hello Prabhdeep,

If you study sincerely in graduation then you can prepare well for CLAT.

For effective study first of all, you should have the concentration power after that you can follow your timetable easily. Also keep in mind while you are making your timetable that it should not be hard to follow it. In starting, your timetable should be easy to follow, then gradually you can increase your study hours with concentration also. To study smartly, you should follow a proper routine of studing new chapters, solving numericals,and revision also in all the subjects. All three things should be the part of your preparation strategy in daily routine.
Your time table depends upon you and your situation like sleeping time, time for other home works or the time in which you are more comfortable for study i.e. quality time for you (in morning, in evening or in night). So, you should make your time table in your own way. In this way, you can prepare yourself well for the examination. Study hours should not be more than 12 hours, it's maximum. 
Thanks for query, you may visit again for further queries. 
All the best for your examination.