This method is preferable if you need to compose one or more pages of text at the beginning of each section or chapter in your PDF file.  You may as well take advantage of MS Word's navigation feature: Table of Contents.  Effectively, Word will automatically create the links to various parts of your PDF, instead of you having to manually create them in Acrobat.

If you are importing images as well as text into the PDF via a .docx (MS Word) file, you can perform compression on the images using Word's tool, before bringing the Word file into your PDF.

Remember that Acrobat is not a content creation tool, so much as a document publishing tool.  The distinction is important, because you wish to create the outline or skeleton of your PDF file in Microsoft Word, and add it after you have assembled and arranged all the contents of your PDF file or document.  Since editing files in Acrobat is not efficient, you want to avoid having to make changes to the PDF once the skeleton, or table of contents, is developed and added to the PDF.  If you need to subsequently make lots of changes to the contents, organization, and the table of contents of your PDF document, you may find it's easier just to recompile your files into another PDF, rather than attempt to make changes to the table of contents of your existing PDF, within Acrobat.  

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As indicated in the video, if you plan to make extensive changes, it may not be worth modifying an existing file.  Instead, you might just compile another, and (re)build the table of contents and section-starting pages in MS Word.

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Resources

Return the Navigable PDF Guide Main Page

Adobe Acrobat's User Guide and Tutorials: https://helpx.adobe.com/support/acrobat.html

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