Starting of the Preparation
To begin with, I joined Vaid’s ICS (in Delhi) and got basic books in June 2017. I had planned to complete the first iteration of optional notes preparation by December 2017.
Coaching was 2.5-month of classes and they covered ~60% syllabus in class and provided material for the rest. A good approach they provided was to break up each topic in a set of questions and write answers for them. This became the notes which can be referred to later. By November 2018, I created basic notes in Q&A format and got it corrected from the institute.