Most study notes die because they try to be textbooks. A useful journal only needs three things: the date, the problem you hit, and one sentence about what finally worked.
I keep entries under 150 words. If an idea needs diagrams, I link a photo from my notebook instead of redrawing it in Markdown for an hour.
Weekly, I skim titles only. Anything I cannot remember gets a second, sharper entry — usually shorter than the first. The archive becomes a map of confusion turning into confidence.
Tools barely matter. A plain folder of text files is enough. Consistency is the whole product.
If you start today, write about something you already fixed this week. Future-you will thank present-you for leaving a trail of breadcrumbs.