How have you been expanding and developing business with existing customers?

Firstly, listening to their needs and making sure they get what they want. Providing a fantastic customer service and being able to listen whenever something happens to go wrong and looking for long lasting solutions to their concerns. Making sure my regular customers are the first to learn about sales opportunities. Designing special offers meant only for regular customers. 

With all of the above and more, I will convert those customers to brand ambassadors and advocates.