If a reader is interested in signing up for your newsletter after reading your blog, be sure to ask him to confirm his email address by sending a test email. This will guarantee that your mailing list is spotless and that all of the people on it are genuinely interested in what you’re sending them.

A double opt-in adds an extra step to the email subscriber sign-up process, asking users to validate their email address and affirm their interest. Marketers have praised and criticized the success of double opt-ins, which indicate a higher degree of consumer interest.