When steps 1-5 above are completed, you will have a magnificent index that literally rivals computer search engines for finding words and phrases in your document or book.

 

This is a lot of work, and so far as I know, only humans can do it, because the extensive topic/concept interrelation and hierarchical context interpretation required for indexing is not available in any consumer-available software that I am aware of.  But there IS (thankfully) software that HELPS in the process.

 

Dr.Explain (for Help Files and HTML-based reference documents), and Adobe PageMaker (for books and printed matter) are two such products I have worked with and have created excellent indexes with, and I can recommend them both.