Your process of documenting what you learn is quite similar to mine Francisco Quintero. Usually, I write about what I have learned on either a book or on a Google doc created for the particular technology or programming language. I love to use my own words when documenting because whenever I come back to look at it, I quickly remember the function of that particular method or technology.
On a Google Doc, I add images, code snippets, and a brief explanation about the code snippet and links to resources that provide more explanation on the subject.
In my book, I draw out a diagram that explains the function of the technology or method, add brief examples of how it works, and when it can be used. For example, when I learn about padding and margin in CSS, I drew a box and indicated effects of either adding margin or padding to a box.
I think it is very important to document what you learn because you would most likely need that information someday.