Inserting footnotes or endnotes is a great way to provide additional information to your readers with a minimum of disruption to the flow of your document. Here is a list of steps to insert them:
Highlight the text you want to reference
Go to the References tab in the ribbon at the top of the page
Click on the Footnote or Endnote command
Choose the type of reference you want to insert (e.g. the footnote symbol)
A reference will appear at the bottom of the page or end of the document, depending on which type of reference you chose