I've heard you should always include a P.S.
What do you think about premiums? Should we make a tote bag?
We have this great program that people love, so I know it will make a good appeal theme, right?
And they are invariably surprised when, instead of the one- or two-word answer they expect, I send them a 300-word mini-essay answer to their simple questions.
Because the simple truth about Direct Mail "rules" is that until you test them on your donors, they're not "rules" at all.
Yes, I -- and any other consultant with a few dozen campaigns under their belt -- can make recommendations based on what we've learned to be true through mountains of experience. I would say, for example, that for most Acquisition and special appeal mailings, a 4-page letter will probably do better, you should include a P.S., and let's have some longer conversations about premiums, programs and what you hope to accomplish.
But those of us who have worked with multiple organizations over the years can also probably point to that one client whose campaign results consistently forced us to toss all our hard-won direct mail wisdom out the window.
You have to start somewhere. So start with the generally accepted rules of direct mail creative. But make sure you test them. Test everything. Test tote bags against t-shirts. Test four-page letters against two-pagers. Test photo-filled packages vs. plain-jane packages. Test different themes. Test, test, test!
Find out what YOUR donors respond to, and you'll have your own set of rules for direct mail.