The help guide is organised in a tree structure, with sections and subsections - in most cases it should be obvious which section and page will have the information you need and also which link will take you to that place.
You can use the Back button on your web browser to retrace your steps, for example to leave a subsection and return to the main section above it.
The Sitemap is a very useful tool for navigating around these pages - it shows you the entire structure on one page, and you can simply click on any link to go to that page. If you ever get lost or stuck, use the Sitemap to find your way again.
You can access the Sitemap through the Tools menu, see the screenshot below: