The basis for a successful PPC campaign is to target the right group of search phrases that you want to use to trigger the display of your adverts. Also make sure that your "call to action" is relevant & strong, that your landing page for that phrase is informative & concise, then hopefully you will begin to see conversions coming through. One of the beauties of digital advertising methods is the information that can be collected to measure the performance of any campaign. One of the most significant factors is the Click Through Rate (CTR), which is a measure of the number of times your advert has been displayed (impressions) against the number of times is was clicked on. By monitoring your results a campaign can be "tweaked" & refined to improve the CTR, poor performing phrases can be dropped as other more relevant ones are discovered.