The two most important things for any exam is maintaining a good exam temperament and a lot of self confidence. It doesn't matter how much time you spend on your preparation, the thing matters is how you prepare yourself on the day of your exam. Keep calm and believe in yourself.
Attempt online mock tests. You could find the syllabus based on your category in the official website. You'll be writing the exam in the middle of the academic year, so you may find questions that are completely irrelevant /untaught, I recommend you to avoid such questions and focus on your strengths.