AussieWebmaster is a brilliant marketer and has offered the following golden nuggets of wisdom on Search Engine Watch Forums:
The key to really tight spends and high CTR is aggressive use of negative keywords.
Most people forget to negative out the long tail terms they create to improve the accuracy of their campaigns.
And it really helps, he says. Those long tail terms can get a "fighting chance" if you only add the negative keywords to it and are aggressive in your campaign.
Check your reports. Make sure you're getting the biggest bang for your buck. As adamap says, "When you couple the negative keywords with the long tail keywords you can really get some strong CTR."
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