I don't understand why people should feel nervous during exams. It is a burden that many people bring upon themselves. I have in my life failed exams. In fact I have been kicked out of my masters degree because of failing a subject 3 times. Yet at no point have I felt nervous or worried about my result. What's the point? If I look back at my academic career, I do not see how being nervous would have helped me pass the exams I failed. It is simply a psychological blockade that people buildup in their brains.

The worst thing that will happen to you is you fail the essay paper. Now I agree its a bad thing and your whole CSS preparation is down the drain if that happens, but tell me one good reason how worrying about it will help you pass? It will not. Only good preparation will help you pass, which I am sure you are already doing. So when you have the pen in hand, consider yourself the best writer in the world and do not worry about the negative consequences. That is for the examiner to worry about.

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'You only live twice. Once when you're born and once when you look death in the face'