hey gaurav,

you must be aware of the fact that JEE mains also has negative marking. therefore,you should be double prepared to answer almost all the questions in the paper. if you want to play safe, try answering 85% of the question paper which obviously is not a walk in the park. you have to work hard and try giving your best. do not get strained. also be cofident. possitivity is also a key to the success. make sure you cover 90% of the syllabus before a week of the exam. so that, you'll only remain with the revision part.never forget to make a notes of every important point you come across. you never know what might help you and when. 

hope this was helpful. all the best.