Advertising in the Google Display Network (GDN) can be a great way to generate leads/sales at a lower cost than with advertising on search networks. The lower cost comes about because the cost per click is often much less on display network placements than on search placements. A common mistake advertisers often make is to run a single campaign on both the search and display networks. This is a mistake because the way to optimize for both networks is quite different. My best advice is to duplicate a campaign and run one version on search and one on display to test them against each other.
When setting up a display network campaign, a shortcut many advertisers take is adding keywords to the campaign and letting Google select where the ads will be displayed based on the keywords. It is much better practice to select your own network placements. If you really want to reach your audience, it is important to target your ads to websites that your customers are likely to visit. If you let Google select your placements, they just match keywords in your campaign to words on the pages and often place you on completely irrelevant websites. To find placements that are relevant to your customers, try using the Google placement tool.
