Here are some tips.
When we edit a subhead, then save on exit, we now have the url for that subhead, which we can cut & paste to use in another article, pointing at that sub-head, or chapter. Alternatively if we are at table of contents, then use links there to get to relevant sub head, then we have the url there which we can cut & paste to place as a pointer in some other article.
When you edit an article, you can break it into sub-heads using
major sub head
use two (2) == on each side of text
use three (3) === on each side of text
and so forth
use four (4) ==== on each side of text
and so fifth
use five (5) ===== on each side of text