I'd decided not to attempt the exam unless I felt confident about my preparation. The syllabus of mains should be finished before prelims so that one may get enough time for revision and updating current affairs before mains. I had to learn the hard way the importance of effective writing, which is absolutely essential for success in this exam or for that matter success in life. Standard textbooks of both foreign and Indian authors can be referred to. In these papers, full details should be given in your answer with diagrams, graphs etc. In the third attempt I laid equal emphasis on GS and optionals and lady luck smiled and I was selected in the IAS.