After the heading styles are applied, it's time to collect them all together in the TOC. This is where Word does the work for you.
First, place the cursor where you want the TOC to appear, usually at the beginning of the document. Then, on the References tab, click Table of Contents, and click either Automatic Table 1 or Automatic Table 2, whichever TOC looks best to you in the instant preview.
That's it! Quick and simple.
When you click in an automatic TOC, it will be displayed in a light blue box. This is okay; it's a visual cue to let you know that it's an automatic TOC. Then when you move the pointer away from the TOC, the entries will turn gray and you will see the cursor where you initially clicked.