First of all self study is the only key to success, that you should know even if you are taking a coaching classes. First thing is to choose one or two (at max) subject that you think is hard for you. Now a subject is chosen, next question is where to study from whether, a book or coaching notes? Its so important to have study material and little guidance. Study material include coaching notes, previous papers, a standard book for each subject. When you start studying a chapter, before that look into previous papers and just get an idea of which topics you feel are important. Make deadline like you have to complete this chapter by evening or night or today or tomorrow accordingly. Once a particular subject is finished, move on to the next in a similar fashion and routine followed with the first subject. Like this in few months you will complete the whole syllabus once. Since you have completed the GATE syllabus once for “almost” all the subjects. Its time to revise them again and again and again. The time taken to complete each subject will decrease exponentially as you do more number of revisions.