To sign up for paperless billing with Northumbrian Water, customers typically need to visit the official website. There, they can find their customer account section where they can log in or create an account if they do not already have one. Once logged in, there should be an option to manage billing preferences, including switching to paperless billing. Customers can select this option to receive their bills via email instead of through traditional mail. It is important to ensure that the email address provided is accurate and regularly monitored to avoid missing any important billing information. If customers encounter any issues or have specific questions during the process, they may want to refer to the website for additional guidance or support resources.