(I was zero in statistics before preparation starts). I have already talked about the initial process in the previous answer. The Research phase. I insincerely started preparing from 8th January 2020 when I was in a hostel in Banaras. I started from Bartle and Sherbert, yes you guessed it right, It was Sequence and Series together with PNC and Probability from NCERT and JEE notes. I used the word insincerely for a reason because it took me 2 months to do this much work.
Then Corona happened.
I was back at my home in Lucknow.
15th March-2nd April - It was the 15th of march 2020 when I wrote down sincerely the two words, "Random Variables" in my notebook. So I consider this date to be the day when preparation started actually. In front of me was my laptop with the book Mood and Graybill opened as a pdf, and in minimized tabs were Hogg and Craig, Sheldon Ross.
Then things flew smoothly, I jumped to Standard distributions. I jumped from one book to another in the starting days. Actually enjoying the learning. Reading more about distributions from Medium. Learning intuition about Poisson, exponential, gamma from youtube channels named Brandon Foltz, stat quest, Zedstatistics, khan academy, etc. It was all fun. Doing questions from Hogg and Craig, and Mood and Graybill's back exercises too. On 2nd April, I was done with RVs and SD's.
3rd April - 22nd April - I picked up Integral calculus which was a prerequisite for joint distributions. Studied entirely from Anton, Bivens with pre-requisite of indefinite, properties of definite from NCERT. 22 April 2020, I was done with Integral Calculus.
23rd April-30th April - I picked up Sequence and Series. Started all over again in a good manner. And finished it on 30th April 2020. Through JEE lectures of Unacademy (for basics). Bartle and Sherbert notes, Schaums Series questions.
2nd May -25th May - Started joint distributions from mood and Graybill only. Questions from Hogg and Craig chapter 2. Correlation and regression from youtube channels mentioned above.
Took a week-long BREAK. :D
25th May-2nd June - Study motivation was inversely proportional to the temperature at that time :p.
3rd June - 22nd June - Started Sampling distributions and WLLN, CLT and finished on 22nd June. It took a whole lot of time. Watched MIT lectures, Other youtube channels to understand more. One thing I want to mention is "I was simultaneously solving 2016,2018,2019 previous to get an idea of types of questions asked" the whole year.
23rd June-30th June - Started point estimation but stopped in 3-4 days as I was overwhelmed with Statistics I guess. And this particular chapter seemed more theoretical. So Stopped it. Took a break! Watched the Family man, Breath series on amazon.
Whole July - At this stage in Maths I had Sequence/Series and Integral. And in Stats, I had Probability up to limiting theorems. Was still overwhelmed so decided to go back to revise stats and pick maths. Studied Differential Calculus one variable only and revised stats together with solving questions of statistics studied till that date slowly and steadily. At this stage, I got to know of P.Sahoo. The gem.
Whole August - I was back in form picking up POINT ESTIMATION. It was a big chapter. Gave a lot of effort to learning, understanding again and again. Mood and Graybill were the best. It completed the chapter as a story of finding UMVUE. UMVUE found the chapter finished. Also asked many questions/doubts to seniors. And cleared them up. Couldn't find many questions from this topic in books so one senior suggested Tanujit sir's notes, another gem.
September - Interval Estimation and Testing of hypotheses. Khan academy for understanding CI, the book Walpore Myres helped a lot in understanding the basics of hypotheses. Again Mood and Graybill covered everything in the syllabus.
October-November-December - This period was over in blow. It was too fast. I don't remember much. On 1st October I thought STATS ✓ But the real game started from this date. When I was completely into solving JAM previous years, Tanunjit's each and every question, WhatsApp groups questions, discussions with friends, etc. I'll say learned more than 60% by doing questions. In Maths I had Matrices and 2 variable calculus to complete. So started doing them parallelly. Started solving JAM maths previous years for maths also. Decided that I'll not do LT because of its low output and high input. A whole lot of things were going on together. Was continuously revising, taking gaps, the anxiety of revision, fear, messed up mind, the chaos of revision, everything was there. On December 20th, I remember I told one of my friends that I can't make it. I was this demotivated. So this also is part of the journey :'). But anyhow took myself back. Also Celebrated everything from Dusshera, Diwali, friend's birthday's to new year's night to my own birthday in January. And these all days were like necessary gaps.
January - Joined a Library nearby. Gave Test Series and did the revision. Solving 2005-2014 JAM previous years. They were pending. And else was done.
February - Solved Gate statistics.
2 February - Gave 2017 JAM by myself.
10 February - Gave 2020 JAM on the official website of JAM. ( Don't do this thing, this late, do it in January for obvious reasons.)
14 February- Gave JAM and was depressed. Later on, got to know that everyone is depressed and I did quite well to get a decent rank.