Set author name and comment color in Keynote on Mac
You can specify the author name and color that are used to identify your comments. Each person uses a different color.
Set your author name
You can change the name that appears in the comments you make in Keynote. The new name appears the next time you comment in a presentation, as well as comments you made previously.
Choose Keynote > Settings (from the Keynote menu at the top of your screen).
Click General at the top of the settings window.
Enter a name in the Author field, then close the settings window.
The name doesn’t apply to presentations that are shared with others. For shared presentations, the name that appears in comments and in the participant list is the name you use with your Apple ID. To change the name (without changing your Apple ID), visit the Apple ID account page. After you sign in, click Edit to the right of your account information, then make your changes and click Done.
Important: If you change the name used with your Apple ID, the name appears in all apps and other locations that use your Apple ID.
If you stop sharing a presentation, the author name in comments reverts to the author name you set in Keynote settings.
Change your author color
Your author color is associated with the comments you add to a presentation. You can change your author color at any time.
Choose View > Comments > Author Color (from the View menu at the top of your screen), then choose a color.
If you have a presentation open, all of your comments in the presentation switch to the new color, and any new presentations you create using the same author name use the new color.
Note: You must add a comment or make a change using the new color to save it in Keynote settings. If you close the presentation without making any changes, the author color reverts back to the previous color.