To start IAS exam preparation, you first need to equip yourself with the basic understanding like the qualification, important dates, subjects and right coaching centers. There are so many books different people suggest the IAS aspirants to study, but going through all of them is not possible.
To give your IAS Prelims preparation a right start, I would suggest you to join a good coaching center like Vajiram and Ravi. The teachers there tell you about the right books, provide you updated study material to help you get maximum benefit from important resources and also provide mock tests as per the latest pattern.
6 important things to know before initiating UPSC exam preparation