You have targeted the user, your opt-in database is getting nicely crowded; it is time to send your weekly free report or newsletter. This is where the numbers are your enemy again. Statistics prove that only 20-36% of emails sent get opened (these are the ones that make it past the spam filters). The rest sit forever unopened in your subscriber's in box. You have to get past the spam filters that email providers have set up, then catch the subscriber's eye, and motivate her to open it, all in less time than it takes to shake a fist.
The basics
First, get past the filters. This can be done by obeying CAN-SPAM rules. They're pretty basic; they include providing an unsubscribe link in your message, and putting in the street address of the business on the email. This does not guarantee that you will get past the filters, but I believe it helps.
Also avoid the word "free," endless exclamation marks, colons and semi colons. This may help after you make it past the first spam blocker. The reason so many people have multiple spam blockers, is to make it harder for your email to be delivered.
Getting your emails delivered is soon going to be similar to rocket science, as email accreditation and the sender's reputation become factors that spam blockers consider. Email deliverability alone is worthy of another topic. But once the basics are satisfied, all that is left is for the user to read your offers.
Be emotional
Again, this comes into play. If you simply put "Power tools weekly report" in the title, it looks sufficiently boring to be put off, and maybe not read at all. Put "Keep your tool maintenance costs below zero" is sufficiently lively to merit a click; a little imagination will generate lively topics. Think "potential life partner" or "I could win a million dollars if s/he opens it," and you will find that emotion comes easy.
Content, content, content
Once opened, the demographics of your user come into play. There are various ways to convince your subscribers to stay, but make sure that you work in a sales offer. If you don't include one in the email itself, work in a link back to an offer on your site.
Content can be interactive; it may be a short quiz with the response linking back to an offer. A quiz such as (a) have you ever used a power drill? "Yes" takes them to a page listing your new power tool, which does literally "everything," while "no" takes them to a page listing things they must know before getting their first power drill.
Your content may just be headlines linking back to your site, but it must be sufficiently interesting. Otherwise you may become a victim of the unsubscribe button, or in a fit of desperation, the "report spam" button.
The eye of the master
Who is in charge of your email strategy? This person can make or mar the response rate for your emails. To risk hurting your campaign, s/he does not even have to write bad copy; considering the amount of email which is competing for your subscribers' attention, average copy is still half as bad as poor copy.
Everything else can be under one office, but everybody in decision making should review email strategy as often as possible.
Be focused
Subscribers, to whom you can consistently send emails which link back to your site, will consistently ensure large traffic to your site. This is the strategy that large content providers such as about.com use. It lets about.com boast of 30 million users, and Yahoo! enjoy the attention of 130 million subscribers. An acceptable ballpark number of subscribers for a large customer database is five figures. This is a sufficiently-sized field for your marketing efforts.
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