Some Key points on how to use Google adwords negative Keywords

Unless you’re using all exact matches for your keywords (i.e. putting your keywords between square brackets like this [keyword]) you should definitely have negative keywords in your Ad Groups. If you put your keywords between square brackets, you will only get impressions on searches for exactly what’s between those brackets, i.e. if your keyword is [red cars], your ad will not be triggered if someone searches for “cars” or “blue cars”.

Exact matches are great, because you can zero in on exactly what people are looking for. However, if you’re only using exact matches, you may be losing out on a lot of great keywords which you haven’t thought of. As a very simplified example, we can use someone selling cars again. Say your keyword is “car” (minus the quotes), if you’re bidding enough, your ad could trigger any search with the word “car” in it. You may think this is great, because now you’re going to get your ad showing up more often, but this is not at all what you want.

To discuss why, we’ll need to go to http://freekeywords.wordtracker.com/. If you’re doing any sort of advertising that requires keyword research, and you don’t know what wordtracker is, bookmark that page now. Wordtracker gives the most comprehensive collection of search engine data currently available.