The Key to Successful Marketing: Your Unique Selling Proposition How to create a simple, compelling value statement that your customers can't resist.

In their book, The Ultimate Guide to Google AdWords, 3rd Edition, authors Perry Marshall and Bryan Todd lay out the fundamentals of Google's pay-per-click advertising system and detail how businesses can build campaigns to increase search engine visibility, capture clicks and increase sales. In this edited excerpt, Marshall and Todd discuss how to identify, communicate and leverage the key to successful marketing: your business's unique selling proposition.

When your small business possesses a simple, unmistakable mission, it stands out in an age of obfuscated marketing messages and Byzantine corporate-speak.

Your ads will practically write themselves and people will line up to buy from you when you have a really powerful answer to these two questions: Why should I do business with you, instead of any and every other option available, including that of doing nothing at all? And, what do you uniquely guarantee?

Your answer is your unique selling proposition, or USP: A statement of value that's so clear and focused it's almost impossible to misunderstand it. It's what you bring to the table that no other business does, or even can.

Your USP is about your product's uniqueness. It's your whole argument for your product, its accompanying services, why it's necessary and why you need it to solve your problem now, rather than later.

A lot of the difficulties people have with Google come from having a USP that isn't clear or even unique. If you have it right upfront, everything from the keywords and ads to the price of your product fall into place.

Your first step in identifying your USP is to answer these questions:

• Why should I read or listen to you?
• Why should I believe what you have to say?
• Why should I do anything about what you're offering?
• Why should I act now?

In fact, these are powerful guidelines for what to include in your Google ad and on your web page when folks click through. Answer them, and you've made your message that much more compelling.

We've all fallen on our faces attempting to be all things to all people. If your purpose is murky and your sense of identity is vague, it confuses your customers.

Perhaps the most famous USP of all is from Domino's Pizza: Fresh, hot pizza delivered to your door in 30 minutes or less, guaranteed. A multibillion-dollar business was built from this unique, simple statement of value.

When you have this message defined and focused, it will liberate you. You become the specialist. Nobody expects you to be an expert on anything other than your one niche.

A couple summers ago we went searching for a solution to an increasingly slow computer. We typed, "my computer is slow" into Google, and this ad popped up: "Slow Computer? www.RegistryFix.com The Problem is Registry Errors. Scan Your PC Now -- Free Trial."

Registry errors are a common problem with Windows, and software that fixes them is widely available. But we'd never seen an advertiser as clear and gutsy as the guy who wrote this simple ad. The diagnosis is uncomplicated, the offer is compelling -- a free and quick, no-obligation registry scan -- and the result is a faster computer. Can't beat that for clarity.

Can you take your message and whittle it down to one short sentence, enough to fit in a Google ad? Can you restate your USP to diagnose a problem, and position yourself as the solution?

Related: 5 Tips to Help Your Marketing Messages Sing

Be different. You'll get the clicks. This is one of the funniest ads we've ever seen: BIG ASS FANS. It could easily be knocked off. But it gets love letters. It gets hate mail. And all the while this company has created a product with broad appeal and an incredibly unique identity.

The company started in Lexington, Ky., as the HVLS Fan Company. It manufactured large, slow-moving fans for giant spaces like warehouses, dairies and factories. The initials stand for high volume, low speed. But it changed its name, and now most folks know the company as Big Ass Fans. And it took its world by storm with some of the savviest guerrilla marketing we've ever seen.

It's just a fan. But Big Ass Fans has created a personality around this product so powerful that it grabs people's attention immediately and catapults its advertising effectiveness into the stratosphere.

More importantly, there's a real economic argument here. A standard fan circulates air at 10,000 cfm (cubic feet per minute). But you need to circulate 125,000 cfm of air, 13 times that amount, at your warehouse. Using 13 standard fans would cost 75 cents an hour, and $18 for 24 hours.

But run just one Big Ass Fan, and you'll circulate the same amount of air for $0.88 a day. This is now part of Big Ass Fans' USP. The question now becomes, can your warehouse afford NOT to put in a Big Ass Fan?

Want to dominate your market? Take your USP, add some chutzpah and give it an unforgettable delivery.

Related: How to Be Unforgettable Online

This article is an excerpt from The Ultimate Guide to Google AdWords, 3rd Edition available from Entrepreneur Press.