Here are some of the steps to set up your personal email address for the xfinity.com login
account.
You must first sign into My Account. Make sure you are on the Users Tab.
You can now choose the Edit option that is listed next to the users for whom you wish to modify the email address.
Next, in the Contact Information area, select Add a personal email address.
You must now enter your email address a second time and press the Save button.
Finally, a verification link for your new email address will be sent to you.