- Preferably you should just use a single <h1> per page — this is the top level heading, and all others sit below this in the hierarchy.
- Make sure you use the headings in the correct order in the hierarchy. Don't use <h3>s to represent subheadings, followed by <h2>s to represent sub-subheadings — that doesn't make sense and will lead to weird results.
- Of the six heading levels available, you should aim to use no more than three per page, unless you feel it is necessary. Documents with many levels (i.e. a deep heading hierarchy) become unwieldy and difficult to navigate. On such occasions, it is advisable to spread the content over multiple pages if possible.