It mainly started in Humanities classes in middle school. I had great History/Geography/Bengali teachers there.
The gist of what they taught me was to optimize writing for one thing and one thing only- clear communication of information. No need to impress or bloat. So that the person grading your test copy finds it the most convenient to read your answer (hence bullet points, smaller paragraphs, etc.), and finds the answer so easily, that they don't dare to deduct marks. India is big on standardized tests, and a total stranger grades your copy.
I used to optimize for grades, and now I do for communication of information. I employ the same things when writing tutorials, documentations, and reports.
I am a reader, and some advices from one/two memoirs of authors I read stuck with me.
I also used to spend 10-20 hours per week on Quora during college, and was in the eyes of admins there, and worked on all sorts of pilot projects. I also had real recognition and multiple thousand followers in one non-English language version of Quora. Practice comes handy.
I also think communication is very important- in teaching, presenting, and writing. So writing is only a part of a bigger part of myself. And communication not in the smelly MBA/LinkedIn kind of way. Communication in its true sense.
I also think that I shouldn’t try to impress or flex while writing. I can comfortably do that because I have plenty other ways to wow people in life. So no word or sentence I use is engineered to impress anyone.
And I always keep in mind that I am selling something. (I have no ties to the publisher or the author of the book here) I really benefited from the book, so I spread the word whenever I can. So, if I can convice 10 people to buy/borrow, and 2 of them read it in full, I honestly believe that they will benefit.
I don't think I am a particularly good writer. However, if you find it good, this is how I do it.