Adwords campaigns usually start with broad match, but any expert knows that if you want take full advantage from available traffic, you should eventually pass to phrase or exact match.
Thus, you can avoid unwanted clicks that can increase CPA / CPL and you'll avoid unwanted impressions that you usually can't identify, but that affect negatively both CTR and quality level.
Many Adwords managers try to avoid creating a specific keywords list with phrase and/or exact match, due to the large effort this embodies.
Let's imagine we have to create a campaign for veterinary clinics in some USA cities. There are two options:
1) Use Broad Match: In this case, writing "veterinary clinic" would be enough, and Google will do the rest of the job for you. You can get some lead, but this will usually work as a magnet for shitty traffic.
2) Use Phrase and Exact Match We let our imagination fly, and start writing…
[veterinary clinic los angeles]
[veterinary clinic in los angeles]
This can be a heavy task. So, to reduce working time, I've created this tool that can produce all possible keywords combinations from text three fields. It's called Keywords Combinator , and you can use it here. It also admits line breaks, just in case you want to make combinations with spaces.
You should consider that the average user writes average of three keywords by search query. This is why you shouldn't create very long combinations with six keywords. If you think your campaign could take advantage of many long-tail combinations, then play with phrase match, or even create different ad groups with different match types, and insert negative keywords to avoid cannibalization.
I've tried this system with many campaigns and the result is excellent. A high quality level and a high CTR allows us to hold 1st position in very competitive keywords.
Please consider there are two types of combinations to hold in account:
1) variations: synonym keywords, or variations in gender and number. For example, “veterinary clinic los angeles” is a variation of “veterinary clinics los angeles ”.
2) permutations: different order in the construction of keywords, or suppression of stop-words. For example, “los angeles veterinary clinics” is a permutation of “veterinary clinics los angeles”.
For more ideas about keywords, please watch this video tutorial: "Introduction to Keyword Research" by Market Samurai