From the Office menu, click the Word Options button.

Click the Display button.

In the Display window, look for the Always Show These Formatting Marks on the Screen section.

Put a check mark in the Show All Formatting Marks check box. Then click OK to exit Word Options.

To toggle viewing nonprinting characters on and off from the Ribbon, you must choose which ones you want to toggle. On the Display page of Word Options, in the Always Show These Formatting Marks on the Screen section, make sure that the Show All Formatting Marks check box is not marked. Then, clear the check box of any character you want to toggle, such as spaces or Tabs. The Ribbon toggle is the Show/Hide button, located in the Paragraph group of the Home tab.

Instead of viewing all nonprinting characters all the time, you can pick which ones you prefer. For example, you might want to see space marks but never optional hyphens. Do this from the Display page of Word Options, in the Always Show These Formatting Marks on the Screen section.