A table of contents provides a quick reference point for your document, giving you the reader a brief overview or outline of where to find what content.
Follow few simple steps below:
Step 1: Prepare your document in Microsoft Word. Make sure the documents has headings.
Step 2: Click on Styles arrow to show the Style windows, see screenshot below.
Heading 3 as my sub headings
Step 4: To put table of content at the beginning of the document put your cursor at the beginning of the document and click Insert tab and click the blank page button.
Step 5: Click on References tab and than Table of Contents. Choose the format you like your table of content to appear and click it.
Quite often you will insert a table of contents and find that you need to change some of the document’s content. Once you do make the changes the table of content doesn't reflect the correct content that is present in the document. To update the table of contents so that it reflects what really is in the document, select it by clicking in it and you should see a tab appear at the top.