Talkers: Figure out who the talkers are in your target market. Who likes to "spread the word"? Maybe its doctors, skateboarders, housewives, or bloggers. Some people like to tell their friends, some don't.
Topics: Give people a reason to talk about you. Maybe you hold a sale, a promotion, give out free samples, or alter your product a bit with a new package, new flavor, or new feature.
Tools: Do everything you can to help spread the message faster. Examples are including stickers and postcards in a box when you ship a package. Go on blogs and post things online. Take part in guerrilla marketing. Hand out samples.
Taking Part: Fuel the conversation! Make sure people keep talking about you by interacting with them. Again, post on their blogs, send them emails, and send them thank you notes.
Tracking: Word of mouth is the voice of the consumer. You can't get anything better than that. Track what people are saying about your product and learn from it.