One effective technique is to personalize each mailing with the prospect's name. A form letter, for example, can be made to look personal if produced on a word processor using a program that inserts the prospect's name and address. There are other ways of individualizing the mailings. Another technique is for salespeople to write brief handwritten notes to each prospect. The note, written in the margin of a preprinted form letter or on the flap of a formal invitation, adds a human touch to the communication.
Direct mail is a medium designed to generate an immediate response.
Therefore, your mailing must give the reader reason to read and act now. For example, it can tell the reader that the envelope contains dated materials. It can stress the importance of attending the show or emphasize benefits. Such a letter should be mailed so that it arrives a few days before the 15th. If you want the reader to RSVP your invitation, you should create a sense of urgency for this too.