I have only one month,for preparation of jee mains exams. How can i prepare.

Hello student student yes jee main exam is knocking at the door. I'm sure if you are preparing of jee main then you're already done with the syllabus it's time to revise each and every thing deeply just go through all your notes daily and solve previous year jee main questions paper as much as you can.
You can also take mock test which will enhance your skill of solving jee main kind of question and boost up your confidence.

Feel free to comment if you have any doubt
Good luck

Focus on solving the problems on your own, do not look for the solutions without attempting a question. Don't spend more time studying new things rather than revising the previous ones. The end result is that they mess up all the things the paper. So devote more time for revision. You will have to study at least 12 hours a day. Give mock tests and try to solve previous years papers.
http://engineering.careers360.com/articles/jee-main-preparation-time-table-for-1-month