The expert's summary is useless to beginners
When I learned to code, I read a lot of expert explanations. They were clean, correct, and completely useless to me, because the expert had forgotten the confusing part.
Here is the thing about expertise: once you understand something, you cannot remember what it was like not to. The confusing part is invisible to you now. So you write an explanation that skips the exact step where everyone gets lost, and you do it with total confidence.
This is called the curse of knowledge, and the only known cure is proximity to someone who is still confused.
What I started doing
Three years ago I started writing down what confused me, in public, the same day it confused me. Not a polished tutorial. Just: here is the thing I did not understand, here is what I tried, here is what finally made it click.
I expected nobody to read it. Two things happened instead.
First, people read it a lot — because a note written on the day you were confused is a perfect map of the terrain for the person who is confused today. Experts write for people who already understand. Beginners write for beginners, and beginners are the majority.
Second, and more valuable: people corrected me, immediately and kindly. Every wrong thing I published got fixed in the comments within a day. I got a free education from strangers who could not resist fixing an error.
Three rules I follow
Write it the day you learn it, while the confusion is still legible to you. Wait a week and you will have become a mini-expert, and the confusing part will have gone invisible to you too.
Say what you do not understand. The honest sentence "I still do not know why this works, only that it does" is more useful than a fake explanation, because it tells the reader where the map ends.
Ship it before you feel ready. The fear is that being publicly wrong makes you look foolish. The reality is that being publicly wrong is how you find the twelve people who will teach you.
The ask
There is something you learned this month that you have not written down. It felt small. It is not small to the person who is three weeks behind you.
Write it today, badly, in public. That is the whole method. Learn out loud, and let the room help.