Promotional postcards should be approached with as much care as you would any other large scale media plan. That initial "one second" with your prospect must have impact to gain their attention and eventual response.
The Headline: You need to create a headline that will stop readers and persuade them to read your piece. Your product benefits should be up front. If not in the headline, then in the subheads. Use bullet points if you have more than several things to convey. Highlight any special promotion or offer you wish to feature. Create copy that sells.
The Visual: Illustrations or photographs should show the product clearly in the best way possible. They should reinforce your message. Will the illustration or photograph attract your audience? Using color effectively can make a big difference!
The Response Mechanism: Do you have a free offer, a consultation, a demonstration, a free estimate, or a trial offer? Then design your card accordingly! To put a time limit on the offer helps the prospect to act quickly. If you're selling something very expensive you may wish the body copy to solicit inquiries rather than an outright sale. That may mean you will have to set up an inquiry handling system at your office. Establishing a Call-Free 800 number has its obvious advantages as well.
Easy to Mail: Statistics prove that postage paid cards bring higher response. However, if your goal is to qualify respondents as much as possible, then the "place stamp here" approach is for you. Whatever you do, make it simple, clear and direct! "Easy response" means easy to complete order forms. Make sure you leave plenty of space for your prospect to write a legible name and address.
Consulting a professional copywriter and art director to create your promotional piece will keep your standards up, especially if you're doing a first-class printing job.