Outlook gives you a handful of generic categories to start organizing your email. You can customize these existing categories, as well as add categories of your own by following these steps:
1. Right-click any category icon in your Inbox.
2. Select All Categories.
3. You will see a list of the existing categories.
4. Place a check in the corresponding checkbox for the category you wish to Rename or Delete and click the appropriate button. Clicking the Delete button will bring up a confirmation message, simply click Yes to delete the category. Clicking the Rename button will highlight the category name. Simply input the new name for the category.
5. To create a new category, click the New button. Input the name for the category, select the color from the dropdown and (if desired) select a shortcut key from the dropdown. Click OK.
6. When you are finished customizing your categories, click OK.