The Worst Mistake I Made As A Student — and How I Fixed It
Throughout my higher education, this remains my worst mistake.

I have made several mistakes.
Mistakes are inevitable.
As any student would, I made multiple mistakes. I sought to attend every lecture (even though, to me, they were inferior to the textbook), I crammed before my exams, I compared my grades with those around me, and so on. I fell into several common traps, but fortunately, I saw them as inspirations for growth rather than as excuses for continued flawed behavior.
While I am grateful for these lessons, I do regret one mistake in particular.
My worst mistake was this.
I took notes.
So many notes. I spent hours upon hours reading the textbook, copying or rephrasing important information, polishing these notes and making them aesthetically pleasing, and trying to force their content into my brain when the exam neared. I had hundreds of pages of study notes, which, by the end, I distilled into about 20 pages to make the memorization process smoother.
All this ended up mattering very little.

Now, how much it did matter depended on the exam format. Some exams were held at home: the task was to write an essay about one of a few given topics, and submit it in three days. In these cases, my notes had no impact but to remind me of some names or theories that I could easily find in the book anyway. Other exams were held on campus: the task was to answer a couple of questions in detail from memory. In these instances, my efforts to write, rewrite, and memorize central concepts paid off decently… but not nearly as well as another method would later on.
Whatever the format, it mattered very little. My method was ineffective.
Popular study YouTuber studyquill once explained this about rewriting and memorizing notes: it is a passive mode of learning. Ali Abdaal talks about it too, in his research-based Skillshare course on how to study for exams: that taking and reading notes are passive pursuits. In a sense, he says, the notes you need are already in the textbook (which also tends to be a compilation of the most central concepts within the field, akin to the purpose of your own notes).
What matters, is to make the learning and remembering parts more active.
It might not be your own worst mistake.
Before we get into the solution itself, I want to note something.
Taking notes is not necessarily a mistake at all. In some ways, by taking careful notes from the textbook or lectures, I did learn a lot of interesting theories and findings. I also made some beautiful documents to go back to if I ever feel like dipping into the past, or if I want to revisit the topic again sometime (though, in that case, I think I’d just go for the textbook instead).
In terms of time and effort, though, taking notes wasn’t worth it for me.

I find it important to mention here that I am a psychology student, so taking notes isn’t very effective for me. However, it might be for students within more practical fields like mathematics, engineering, or design. Keep this in the back of your mind: that taking notes could be effective for you even if it wasn’t for me.
But it was mine — and here is how I fixed it.
In the end, I ended up wasting a lot of time and engaging very little with what I was pulling out and taking in from the textbook.
I spent too many hours taking notes that either (1) ended up practically unused during the exam, and which were subpar to the textbook anyway, or (2) were tiresome and difficult to commit to memory because of the inherent passivity of the study method. It was only once I learned about and did the following method (all from Ali Abdaal’s course, to credit him) that things changed. Suddenly, I was spending much less time getting through each chapter, and in turn, I learned a whole lot more and carried much larger loads of information into my exams, with much more ease.
I learned Active Recall, and it saved so much lost time and fruitless effort.
I have a separate article that goes into how Active Recall is done, but its benefits are worth mentioning here too. Active Recall is highly effective because it relies on asking and answering questions rather than writing and memorizing notes. As Abdaal states, it is a more active approach to learning that helps you commit information to memory whilst properly processing it (rather than merely receiving it from the page, repeating it, and hoping that it will stick).

This was how I grew from my worst mistake as a student.
No longer was I consuming information passively, or spending hours grinding through hundreds of pages that contained the more complete version of my notes anyway. Now, I could focus on properly learning and digesting the information that I would need to access during my exams at campus with Active Recall (by internalizing and saving rather than forcing the information into my mind). Thus, I could spend my time more wisely to prepare for my exams at home as well (by using more effective means of engaging with the material without merely copying it for no reason).
Now, I could finally learn.