As covered in the section on gaining clients online, this often-overlooked method is easy to set up and very powerful once a list has been built. Using Mailchimp, Aweber, and other mailing list managers, you can use build a list of interested visitors and clients and periodically send them useful information and offers, converting a percentage of those to new orders.
You can use the automatic responder features offered by these services to send a chain of emails spaced out over days and weeks to new sign-ups, including any attachments or messages you may want to convey. These are extremely effective at keeping clients and prospects engaged.
Using a reputable service is important as many are flagged for spam and have trouble delivering messages, despite their legitimacy.