Maintain focus: Though Reasoning Ability is the key section you should prepare for all the three sections equally. Play to your strength areas, but do not leave other sections behind.
Increase speed: Distribute your time well between all three sections. This can be done if you understand and improve the time you take to attempt each question.
Improve accuracy: With the application of learnt concepts, you need to keep improving your accuracy. Since the syllabus is huge, it is tough to cover all areas equally few days before the exam. It is, therefore, necessary to go through important areas once more, before the exam day. This will boost your confidence as well.
Take mock tests: Take as much as mock practice tests as you can. There are dedicated apps for JEE Advanced 2018 by which you can practice either full exam or a section of any particular topic within the section at your convenience and improve your performance.
Don’t waste time: During the day we end up spending quite some time eating, resting, bathing or just relaxing.When there is very little time left for an examination which might very well change the course of your career, it is crucial to not waste it. It might be hard, but highly beneficial if you can just fill the empty spaces of your next couple of days by memorising important formulae, years, concepts, etc.
Solve previous years’ papers: Though the exam mode has changed from offline to online, the assessment areas of candidates have not. Practice not only previous years’ papers but also new questions available.
Build confidence: Often, unsteady nerves won’t let you perform well despite a good preparation. It is very important to be confident and steady before your exam. If it is hard to calm down, just try a few breathing exercises. This will help you relax immensely and boost your exam day performance.
— Youth4work.com