Cross reference wording, placement, and formatting are important considerations, but there are few rules. It's both a style and content question.
It's true that appearance, wording, and format might be prescribed by an organization's or publication's style guide. You can consult Chicago Manual of Style, Microsoft Manual of Style for Technical Publications, the Apple Style Guide, and so on.
In terms of content, I believe there is a difference between making reference to another section or chapter, and telling a reader to go to another place for specific information. The difference may only be in whether you are mentioning what is in a chapter, or directing a reader there for specific information related to the current paragraph or section. For example:
The Safety chapter (page 21) includes a list of toxic substances that are involved in the cleaning process.
Before continuing, refer to "Safety" on page 21 for a list of toxic substances.
For more information about hazards, see "Toxic substances" on page 27, and the entire chapter on safety ("Stay Safe in the Factory" starting on page 11).
I always go back to what I think are the fundamental rules of technical and informational writing: Be clear, concise and consistent. If you think the added words or a specific format are clear and concise, then use them, whether the cross-references are for print, or hyperlinks.