When people search the web, they tend to use specific phrases like "yoga studio in springfield", rather than general ones like "yoga". So, when it comes to selecting keywords, be specific, and keep your ads (and budget) targeted to the most interested people.
Ads, like keywords, help people decide if your business is what they're searching for. If you offer several different products or services, try creating a unique ad for each one. A yoga studio, for example, might want to create one ad for beginners and another for more advanced classes.
AdWords makes it easy to put your message in front of people anywhere in the world. But what if you're only interested in potential customers within a 10-mile drive? No problem: you can use geo-targeting to show your ads in a particular area, whether it's a city, region, country or specific distance from your business.