Johneltin
Learning basic HTML (The allowed HTML used in EPUB barely scratches the surface of what WEB designers do wit it
) is excellent advice.
Sigil color codes things to make some of it easier.
But first, if you
have heading levels defined, and they are just in a mish-mash of levels, Sigil has a couple of ways that can speed things up.
Saved searches has a section that includes Promote or Demote ALL headings. I use commonly that to set all headings to the most frequently used level (usually 'Chapter') .
Now I use the TOC editor (bars icon) to
raise individual lines (select, then click the arrows)
My standard is: h2 for
Part, h3 for Chapter, and for Anthologies, h1 for book-story (only if h2 is needed because one book has a
Part used
Lets face it, if your headings are a really wild jumble, you will need to learn REGEX fairly soon.
There are a couple of threads here at MR. I would start with the one by Manichean (that was the one that turned on the
for me) ,Then there is the one with the cute name: TranasaurusRegex for solving specific problems