Dear Pranusha,

You can join coaching classes for Gate. Apart from that everything that you are studying now is included in Gate so start orepsprep notes. Check the syllabus for your respective subject and find out which topics might be your weak point. Try clearing all your doubts in that subject with guidance of your teachers. Prepare a timetable and manage your time for current studies and for your gate preparation. Try solving mock tests from classes or from the one that you get online. 

All the best!