There is a standard formula used in all marketing called AIDA: Attention, Interest, Desire, Action. This formula is especially true when writing copy for a direct mail piece.
Attention
The rest of your copy doesn’t matter if you can’t get a reader’s attention. If you don’t have their attention, they won’t continue reading. It is the marketer’s job to cut through the competition, who is also vying for the attention of the reader. You need to scream something! It could be a powerful offer, something odd, unusual, even controversial or emotional. You can use words and/or pictures as well as design. Tune into the reader’s point of view and think extreme!
Interest
Grabbing the reader’s attention is just the first step! To keep the momentum going, you must be interesting. No one has ever been bored into a sale. Since your direct marketing piece will be targeted, you will probably know what peaks your reader’s interest. A sure way is to make a promise or offer. The wording should promise or create a situation that is more desirable than the way things are now.
Desire
Make them want it and you’ve got it sold. It means having just the right irresistible offer. A focus on the benefits is important when creating desire. When prospects see what you are offering could and will change their lives, and they want that change, you have scored with desire.
Action
Call to Action: This means telling your prospect what action to take and how easy you’ve made it for them to do so. This is your opportunity to be as compelling and direct as possible. Ask the reader to do something– call a toll free number, or meet you at a grand opening. The more specific your call to action, the more successful it will be in generating response. Action implies results and that is what your prospects and you want.

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Chris Tackett