In order for Brand and Sign to be able to apply branding to your outgoing email accurately, we need certain information to do that. As much as we want to believe it sometimes, we are not mind readers. The first, and most basic thing we need to know is, whose outgoing emails do we actually need to brand.
To that end, the Addresses page allows you to give us that information. You can add these Addresses one-by one, all in a big list from your favorite spreadsheet program, or just imported from your Google Apps for Business account.
An addresses first name, last name and job title are some optional details we ask for, so that when you setup the consistent signature for your domain, we can apply those individualised details for each of those people. In addition, you also have the flexibility to uniquely identify which addresses should be branded by a specific banner campaign by allocating them to that campaign.