You needn't have a Melanie or Ken working for you. To take advantage of an offered discount, the customer must provide a numerical or verbal code. For phone or Internet sales, the buyer reads back or types in the number. For mail order or retail shops, the buyer needs the coupon that contains the code. For radio and TV ads, use this method instead of the code.
Someone gets a free imprinted T-shirt, mouse pad or hat if they come in and ask for it.
The number who ask indicates the effectiveness of the station that aired the corresponding ad. Print ads or e-mail ads with a call to action can send respondents to a Web page set aside just for that version of the promotion. An address variation. Check with your post office before implementing this. In many situations you can add a suite or box number to a street address to reveal which ad version prompted the order or inquiry.