There are a few different ways that you can add an outline to a PDF for free. One way is to use a PDF editor such as PDFescape.com. With this method, you can add an outline by clicking on the "Bookmarks" tab and then clicking on the "Add" button.
Another way to add an outline to a PDF for free is to use a PDF converter such as PDFtoHTML.com. With this method, you can add an outline by selecting the "Outline" option from the drop-down menu.
Finally, you can also add an outline to a PDF using Adobe Acrobat. With this method, you can add an outline by going to the "Document" menu and then selecting "Add Bookmark."
