The best time to prepare for the UPSC examination is to start from the 2nd year of college. This time is the high time and if you can prepare sincerely then you can really crack the examination after passing your course (if its a 3 year course). A preparation of 2 years is said to required in order to crack the examination. Having some coaching or guidance can be really helpful for a student.

Now the study schedule for a self study candidate must be set by the student itself. Atfirst the student should have the hardcopy of the UPSC Syllabus. Then you should set targets as per the topics mentioned in the syllabus. The target should contain a pace such that a topic must end by the end of 1 months. This way, based on your ambition and ability design the daily schedule for yourself.

Also you can consider, seeing the tips and guidance on youtube by the toppers which can really help you out.

For UPSC Preparation tips, read the article provided below:

https://competition.careers360.com/articles/how-prepare-for-upsc-ias

I hope this helps. Wish you a great eve!