There are prep courses for the GATE exam. Do an online search for "gate prep" and you'll find free prep tests for the various levels. The exam assesses your prior learning; the prep course will help ease your nerves so that you can do well.
Don't be nervous. Be prepared. The former is not helpful; the latter is. There are GATE prep books and a GATE prep group at Talk to your academic advisor, too for suggestions on how to prepare. You also want to increase your ease in taking the exam.
I would say the thing you probably heard from many people that is study and dont stress about it, Also to get enough rest and to eat before you take your exam. because being tired and hungry is just an easy way to fail your test. hope you do well good luck
The best preparation is performance preparation, so that you will not be unduly nervous day of. Take practice exams under time pressure, review your mistakes, and repeat. Best of luck.