Before start any kind of preparation you must know the syllabus of that particular exam which you will going to attempt.. As we all know the process of the UPSC Civil Services Exam is conducted in three phases –
Stage 1: Preliminary Examination (Objective)
Stage 2: Main Examination (Subjective)
Stage 3: Interview (Vocal)
Now work according to the syllabus give time in your studies don't waste ur time .. make a proper study schedule and do accordingly . Read the NCERTs (class VIII to XII) for History, geography, Science, Economy and Polity which sharp your mind andit will help you in exam and Always keep your mind open to knowledge - through newspapers, tv...etc If you come across anything new and interesting make a note of it. it could be useful for UPSC exams (in prelims, mains or interview)..