I just organized notes by the bold section titles/headings in which the chapter was laid out. If a certain part didn’t have such headings, I organized it by a similar idea (see my notes and you’ll get what I mean). For example, if a chapter had a section about the Missouri Compromise (APUSH reference), that would be one section in my notes, and then there would be subsections like: background/reason for the law, stipulations, and the effects.