Before you begin preparation, the first step should be knowing this examination completely and all it necessitate at each stage of the examination.
The next stage is self-assessment that will help you measure where you stand and how much effort is needed to reach the level, this examination entails. This exercise would also figure out your strengths and weaknesses thus you will be able to plan your strategy better and will be able to prioritize the areas that need greater effort.
Adopt an integrated approach and commence preparation with Main Examination orientation.
Being in 3rd year, you have enough time to prepare; so, first strengthen your basics and advance gradually with standard text-books and relevant study-material.
It is good sign that you are clear about your choice – History as optional subject and this would render some help in taking care of History constituent in General Studies syllabus.
In recent years’ UPSC has shown inclination towards current events and contemporary developments; so, cultivate newspaper reading habit and prepare self-notes.
Make a beginning; you will keep on getting insights about preparation and we are always with you to motivate till you reach your destination.
All the best!