Every other has their own way of preparing for competitive exams. I can share some of my views- hope it could turn out to be a tip for you.
- Select the best material for the prep and stick to it and don't change or refer other books.
- Make a timetable but make sure it's not hefty(6-10 hours max) and give time for your other hobbies or things you like.
-Discipline is a must. don't procrastinate things you scheduled according to your timetable.
-Always take short breaks like 5-10 min every couple of hours.
-Mock tests, take as many as them. if you search you can find free tests online. and don't back off taking tests coz you haven't prepared or covered the schedule you've made, you'll never be prepared enough for the competitive tests.
-Motivate yourself. trust me no motivation stays longer. so you have to find more ways to keep yourself motivated always.
-Revision is the only best thing to remember the topics. People say you shouldn't memorize for competitive exams, but in some topics, you won't find alternatives.
All the best for your preparation.