Writing sales letters and brochures is both an art and a science, says Tony Attwood of Hamilton House Mailings. It's important to have a sense of both. There are only four ways of writing a direct mail ad that will raise your response rate.

1. Sell on price
This is the oldest approach?and it works if you are really sure you are less expensive than anyone else and you are sure that your audience is not concerned with quality. Of course, there's a downside to selling on price alone. The problem is that it can get you into a competitive price war, with negative results for both you and your competition.

2. Headline a benefit
This is on page one of every marketing book. But vast numbers of direct mailers still sell on features. Benefits are things like "No more back ache when you spend all day at a desk," or "double the speed of your broadband at no extra cost." Unfortunately, many still ignore benefits and promote features.

3. Ask and answer an interesting question Pose a question that you think could be interesting to your reader. Spend a paragraph or two developing the question and the issues around it. Then answer the question. All the way through this, don't talk up your product or company name; instead, have as close to a conversation as you can get in direct mail with your potential customer.

As an example, consider this headline: "What's the simplest way of doubling the response rate in direct mail?" If direct mail is your line of business, you have to read it, even if it is just to prove "I'm already doing that."

4. Use humor
Humor is widely used in radio, television and particularly cinema advertising. But it is hardly used at all in direct mail. A good starting point is to present yourself at one with your audience, and share with them some sort of issue that annoys them. So if you are a business-to-business service, look at the company's day-to-day work, find the thing that really annoys them and raise a chuckle through it.

Two Bad Approaches. What Not To Do

1. Announcements don't work.
Announcing in a headline something like "ABC Ltd launches the XYZ laptop version 2" is close to useless. If you then proceed to tell the reader that you've been in the computer business for 20 years and the XYZ is the very latest technology, then you can be sure no one will read it. Don't talk about yourself?talk about the reader and his/her wants and needs.

2. Grabby images don't work.
"Grabby" images are graphics that aim to capture the readers' attention in a gimmicky way. Grabby images are everywhere: direct mail, TV, newspapers. And yet, they simply don't work.

By Tony Attwood, chairman of Hamilton House Mailings, UK, for MarketingProfs.com