Office 365 (Outlook) - Create and Assign Color Categories to Messages
To assign a color category, do the following:
- For a message in your Inbox or any message list, right-click the message, hover over Categorize, and then click a color category.
- If you have a message selected, you can choose a category by clicking on the Tags button on the top ribbon and then selecting Categorize.
The first time that you assign a default color category to an item, you'll be prompted to rename the category. You can also change the color of the category and choose a keyboard shortcut.
For the most current and detailed information on creating and assigning color categories, please reference the Microsoft support page https://support.microsoft.com/en-us/office/create-and-assign-color-categories-a1fde97e-15e1-4179-a1a0-8a91ef89b8dc?ui=en-us&rs=en-us&ad=us.