See..i too prepared for neet without coaching and scored 651 so i think i could be of some help to you:-)
Long one ahead….:-D
First i was from ISC (11th and 12th)..so the concept of Ncert was very new to me.I started reading bio ncert after my 12th boards last year.Due to covid exam got postponed and so i decided to study something for my first attempt.I read bio ncert and watched Dr.Anand mani’s one shot videos on unacademy (free) and kept revising.For physics i made notes religiously from the crash course (free) on NEET PHYSICS KOTA youtube channel.For chem,i read chapters like biomolecules,surface chem,chem in everyday life to score and since i had given my boards (though isc) i had ideas of physical chem’s formulas. So this made me score 437 in neet 2020 with an AIR of 1.5lakh. I too had joined Neetprep achiever batch test series for giving tests.
Now my drop year story…
I was very clear in my mind about taking a drop because i knew that without full preparation i scored 437 so i can score good enough to fetch me a medical seat if i work hard.
So now to the question..how to prepare for neet without coaching..i will tell you how i did-
Bio— NCERT. I used to read 2 chapters per day for the whole year. When exam approached near this increased to 4–5 per day. So the thing is consistency. Everytime you read ncert,you will find a new line. I think that’s the beauty of bio ncert. Just focus on revision. I solved MTG at your fingertips. My experience with the book is that it contains many out of ncert ques and topics. Use it for ques practice and don’t bother about the extra content there. My score in bio was —356/360
Chem— physical- I watched all the old videos of alakh sir PHYSICSWALLAH (free) and made notes. Practise questions from ncert,examples,test. Learn the formulas. Inorganic- NCERT. I made notes and sheets of the data from ncert and keep revising them. Nothing in the paper will be out of ncert. Solve questions. Organic— I made notes from alakh sir’s old videos PHYSICSWALLAH ( free) . Make sheets of all the reactions in ncert. My score in chem was 166/180.
Phys— I solved DC Pandey for ques practice. Ummed series PHYSICSWALLAH, COMPETITION WALLAH (free),free dpps were also available on the app. I solved each one of them twice. Ncert examples and excercises are a must. My score in phys was 129/180.
So this was how i prepared for neet without coaching.
I also bought allen test series but my marks never crossed 600 except the last test in which i scored 628. The last test which i gave was of akash (free) in which i scored 677. So this fairly depicts that your test’s marks does not guarantee your performance on the D-day.