Is a long subject line better than short? Do green envelopes do better around Christmas? Is a postcard enough copy?
There’s no reason to guess!
Instead, you can apply tested principles in preparing your promotional materials that increase their effectiveness. Advertising legend Robert Collier called it “taking the guess out of advertising.”
Collier understood that writing advertising copy (or any form of persuasive material, for that matter) should be something of a science. He liked to refer to the work of the Tested Selling Institute and Word Laboratory Inc., which identified words and phrases salespeople could use to get customers to buy. These “Tested Selling Sentences” were to be memorized and used by salespeople in one-on-one interactions with customers.
Collier believed that taking this kind of approach to selling would be just as effective when applied to the printed word. For example, his research showed that in writing sales pieces, there were certain tested openings to letters that would invariably win readers’ attention, which, of course, is the first step to making a sale.