The number one thing that nearly every successful online entrepreneur has going for them is that they have an email list. This is a list of subscribers that opted in to receive more information from you, to gain access to free training, or people that bought something from you. At one point or another we have all made our way to an email list. From the largest online retailers to the solopreneurs running a business from their living room, email marketing is still the number one way to engage and follow up with your audience.