Brands are designed to be flexible and you can edit or change a brand after it's been created.
Note: Changes made to a brand will impact future emails for any sequence using the brand.
To edit your brand go to Account Settings and once the Account Settings open, select the StickyEmail tab.
This will slow your list of Brands that you have.
To edit the brand start to type in the brand, changes are automatically saved.
Here is a GIF showing how to edit your brand.