Making Your Yellow Page Ad Pay Off   With about 80% of CPA firms using yellow page ads and spending several thousand dollars a year on them, getting your ad to stand out is important.   Here are some do's and don't's: Don't use your firm name in the headline. Do use some headline (or the most prominent portion of the ad) to grab the reader's attention and to point up what you do and how you're different. Don't cram the ad. If you do, people will shy away from reading it. Leave plenty of "yellow space." Do include a "visual" (e.g. logo, line drawing, etc.) to direct the eye of the reader to your ad. Do make sure the telephone number is large enough to be easily readable. Do include your street address in the ad--yellow page shoppers "shop" location. Do consider an accent color. If you're the only one, it should more than compensate for the additional cost. Do think about other headings in the phone book that may be appropriate (such as tax preparation). Don't he afraid of attracting too many small clients; that will sort itself out. The important thing is to make the phone ring! Do track the ad's effectiveness by asking all new clients how they heard of you or your firm.   Martin Reports