Direct mail is sometimes referred to as direct response advertising. On one level, that refers to the idea that the response goes directly back to the mailer. You send out an offer, and you get back orders. Or perhaps you send out a fundraising request, and you get back donations. On another level, though, direct can be used as a verb, as in directing your respondents to do it in a certain way.
Think about that for a moment. What exactly do you want people to do when they see your mailer. Obviously you want them to read it, but what next? Do you want them to call you? To send you an e-mail? To visit your website? To visit some physical location?
Here’s the point. If you make it clear what you want them to do, you have a better chance of having them do it. If you want them to call, make the phone number stand out, and include the words call us at! If you’d rather receive e-mail than phone calls, make the e-mail address stand out, and consider not even printing your phone number. If you want them to visit a physical location, include a map!
As in most things, clear is good with direct mail, and anything less than clear is not.