When should I start taking mocks and sectional tests? I just bought the course the

You can see the leaderboard consists of familiar names. Sectionals are key to getting used to the exam. So, take as many sectionals as possible and start early. Also, make sure to analyze the sectionals, just don't take the tests just for the sake of taking tests. One size doesn't fit all. Toppers preach taking as many as 50+ sectionals in one section. So, get started early. And as already mentioned by one of the faculties at Cracku, take a mock every week and analyze it thoroughly. It will help you to focus on the the places you need to work on. On the contrary, if you never take tests, you'll never find your strengths and weaknesses. So, start now, it is the right time.
Thanks.

Cheers
Vergil

start giving early as possible and study where you lack,dont get caught up in the age old thinking of "pehle padhunga,fir test dunga"

asap rather than waiting for syllabus start 1 mock a week to do away with anxiety of mocks

Try one mock or pyq to check where you stand or to get overview of the exam.