In order to score good marks in JEE Main make sure your concepts are clear. To make your basics strong you should throughly read NCERT books. So, that you can easily solve tricky questions then you can refer your coaching material.

You can make your time table. So, that you can complete your course and you get proper time for revision. You can make your time table according to your strength and weakness. Set your daily and weekly targets and try to acheive them.

It is important to focus on the topics which carries more weighatge in the exam  

You should refer previous year papers to know the exam pattern and level of questions. Solve MCQs for your practice. You should also solve complete mock test series to work on time management, to analyze your preparation level and to know your strength and weakness. So, you can work upon them. 

Revision plays important role in scoring good marks. Make sure you revise all the syllabus properly. You can also make your important notes and flashcards which will help you in revision.

Be motivated and self determined. Prepare well for your exam.

All the Best!!