Hey Sourab.

GATE for the major part concentrates on the core subjects which are more likely to be taught from your second year or may be second semester. As of now concentrate on semetser exams and prepare for the caculus and aptitude part of GATE exam.

Go through previous years GATE papers see which core subject carries how many marks or questions and try and focus specially on those topics as you go through every semester. You can even make seperate notes for those special topics and save them for later when you would giive GATE in your final year. Save your notebooks and textbooks for the same.

hope this helped

all the best