To make it even more valuable, practically nobody uses it. That is why it's still a secret. What is it?

It is a face.

Everyone loves to see a face. Even your pets like seeing your face. Look at all the ways in which people are attracted to faces. A few decades ago, there was the Potato Head craze. Later, the Pet Rock took us by storm.

People wear the face of favorite cartoon characters as charms or on tie clips. We are used to receiving “smilies” in Emails and dashing off a smiley face on a note we write.

Here are 5 ways you can use a face to sell your product:

1) If you have a Web site, include snapshot of yourself. It builds instant trust. Buying and selling is a personal matter and customers like to feel they are dealing one-on-one with a real person.

2) Place a picture of a person on your product. It can be on a book cover or on packaging. Researchers discovered that viewers are most attracted by a face that is looking straight at them – eye to eye.

3) For an advertising piece, such as a mailer or a postcard, a pet's face is very effective. It can be used for any type of product – not just pet products.

4) Testimonials are powerful buying triggers. Would-be buyers believe others who have already bought. Make your testimonials even stronger with a picture of the testimonial giver.

5) A child's face is a winner. A few days ago, I saw a man selling a filtration system on television. He held a little boy on his lap as he spoke. Without mentioning the child, he spoke of the benefits of his filters. Seeing that little boy's face, you knew you needed that filter to protect your own children.

Bottom line - put a face on your product as soon as you can. Your marketing will come alive and good things will happen.