When it comes to managing your pay per click campaigns there is perhaps nothing as important as negative keywords. You can wing it and try to find the right negative keywords by trial and error or you can be proactive and let your tools do the work for you. But you’ll need to ensure that your negative keywords are the proper keywords for your campaign and that they make sense for your campaign.

Negative keywords can save you a lot of money, especially if you use them judiciously. Perform a keyword search for your most valuable keywords and see what related keywords are returned as suggestions by your keyword research tool. Scroll through and see what keywords are not related to your niche. For instance, if you are running a campaign for “red hat linux” and you search for that phrase you’ll likely get some related keyword suggestions for other red hats like derbies and pillboxes. Since you are selling software, not fashion trends you’ll want to include those in your negative keywords list.
Sometimes, however, you’ll find yourself getting found for keywords that make sense. For instance, by checking your analytics package you find that you’ve had a handful of searchers come to your site after searching for “red queen mad hatter”. You know that has nothing to do with Linux so go ahead and add it to your negative keywords list. That’s one more use that your analytics package has for you and it’s a huge benefit.

I realise the importance of negative words, what I dont understand is how to effectively use them. I mean if its for a town its fine but lets use your “red hat linux” example above. If I choose the broad term cap, from what I have seen by the filter we have installed on our analytics cap might also include hat as they are “broad”, so I might be loosing hat and then my negative words have impacted on my results. If I use the exact word not to include my negative list could contain thousands of words as we know that people are searching long tail or at least buyers are. Hope what I am saying makes sense, what do you recommend as a strategy.