Hello Dear,

if you are CSE student and want to prepare for GATE exam then there are some rules that you can follow - 

1. Cover up the syllabus and your core subjects.

2.solve previous years papers - online material available.

3.learn from online - Geeksforgeeks, rabindrababu(youtube channel) etc.

4.give mock tests and evaluate yourself - https://testbook.com/gate

5.pin point your week areas and work hard on these areas for stong.

note - consistency is the key to success.

good luck