The first attempt of the candidate is a very crucial one and that is the attempt in which we can give the attempt with full confidence. You should not waste this opportunity for just a sake of writing the Preliminary examination. In order to clear UPSC exam in his first attempt, one has to follow proper strategy. Careful planning should be there to achieve something in the given circumstances within a certain time frame. On thinking about the strategies to become a civil servant in the just first attempt, the foremost idea that comes to our mind is that one should start preparing with sufficient time and hard work. Only then you will be able to clear UPSC in first attempt.
Institute can be good place to spend sufficient time between the study environment , where you can get time to do hard work and proper guidance and improve your skills. You can go through good institute like:
Sriram’s IAS
Chanakya IAS Academy