You should make your  time table. So, that you can complete your syllabus on time and you get proper time for revision. You can include daily and weekly targets as well.

To score good marks make sure your basics are clear. So, that you can easily solve tricky questions. Make sure you complete your NCERT book first to make to build your fundamentals.

You should focus on the important topics which carries more weight-age in the exam to score good marks but make sure you complete your whole syllabus as you have enough time.

You can refer previous year paper to understand the exam pattern and level of questions. 

Practice plays a important role in JEE exam. Solve as many as mock test series to analyze your preparation level at regular period of time. You can solve MCQs and timing test to increase your speed.

Revision plays a good role in scoring good marks. Make sure you revise your whole syllabus before the exam you can take help of notes for revision.  Do revise all the formulas. 

All the best for your preparation and exam!!