Using styles means that you can easily create a table of contents (TOC) in your word-processing program.

For example, to make a TOC in Microsoft Word (Microsoft Office 365):

1. set up your heading levels and apply these styles consistently to the relevant content
2. go to the page where you want your TOC
3. click on References > Table of Contents
4. select the type of TOC you want, or create a custom TOC.

Word will automatically create a TOC on your chosen page using your heading levels.