Numbers
You can specify the author name and color that are used to identify your comments. Each person uses a different color.
You can change the name that appears in the comments you make in Numbers. The new name appears the next time you comment in a spreadsheet and for comments in new spreadsheets, and it changes the name that appears on comments you made previously.
Choose Numbers > Settings (from the Numbers 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 spreadsheets that are shared with others. For shared spreadsheets, the name that appears in comments and in the participant list is the name you use with your Apple Account. To change the name (without changing your Apple Account), visit the Apple 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 Account, the name appears in all apps and other locations where you’re signed in to your Apple Account.
If you stop sharing a spreadsheet, the author name in comments reverts to the author name you set in Numbers settings.
Your author color is associated with the comments you add to a spreadsheet. 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 spreadsheet open, all of your comments in the spreadsheet switch to the new color, and any new spreadsheets you create using the same author name use the new color.
If you’re using iCloud when you make the change, any spreadsheets you shared or joined when signed in to the same Apple Account are also updated with the new color.
Note: You must add a comment or make a change using the new color to save it in Numbers settings. If you close the spreadsheet without making any changes, the author color reverts back to the previous color.