Many sites require only an email address; all other personal information is optional. Second, there should be several sign-up opportunities on a site, including on the inquiry, order, and feedback forms. These forms may use a checkbox asking prospects if they would like to receive occasional special offers/newsletters by email. If so, it must be placed conspicuously on the form. Third, a privacy policy that addresses what will be done with user information should be posted in an obvious place.

Continuing on the lines of “opt-in” marketing, one of the most successful methods is the double opt-in technique. In double opt-in a user elects to receive email newsletters or standalone commercial messages. A confirmation email is sent to that user, who is now required to take one more action to be included on the list. The person must click the link within the confirmation email to affirm their intent to join your mailing list.

Although, the double opt-in techniques runs the risk of losing subscribers during the confirmation process, it gives the subscribers more control and thus, has proven to be more successful. That said, here are some measures emailers who practice double opt-in can take to reduce confirmation drop-offs. When a user enters his address, mention an email will be sent to him and include its estimated arrival time. Indicate the user is required to respond to that message to receive subsequent mailings. With transactional customers, consider placing this information on the page with order confirmation.

Ideally, a confirmation message is sent immediately. It should be sent while the subscription is fresh in subscribers' minds and they're still engaged in an online session. If you indicate it will be within a day or two, make sure you follow through on that promise. If your systems are slower, then requirements related to message content are even more relevant.

If you need a confirmation, that's the only thing you should ask for. Explain to users they will not be added to the list until they take the necessary action. Most desirable is a one-click confirmation link embedded in the message. Giving users a reply option with subject line intact is another good approach. Requiring them to write something in the subject line or body of the message or asking them to forward the email on to another address is not nearly as effective.
Ensure that your contact information is included in the confirmation message and, if possible, include a link to your privacy policy.