It would be better if I could get an idea about your current preparation status as you have not mentioned the same so I am assuming you are done with your syllabus so after that you can follow below tips -
It is advisable to solve previous year question papers as these would be helping you to know all the important topics and questions. Once you are done with these, you can devote maximum time of yours in online mock papers as this is one of the best source to know where all you are still lacking and what all topics you need to revise and apart from this, these are also very helpful to know the actual exam pattern and will also teach correct time management skills during the exam.

Hope this helps!!!