Bill Glazer is a man on a mission. He wants everyone to “get waisted.”

No, it’s not a misspelling and, yes, I’m having a little fun here. But so is Bill.

After running a small fashion boutique in Lauderdale-by-the-Sea, Fla., Bill started noticing that his customers were complaining about the burden of carrying all their stuff. He thought about this and, like many successful entrepreneurs, decided to come up with a solution to solve the problem. His solution: a two-pocketed belt-like spandex carrier that fits just below the waist. Glazer calls it the “unfanny-fanny pack.” I call it genius.

But as genius as it is, it still needs to be sold. Many would-be small business owners have come up with plenty of smart ideas, but that doesn’t necessarily mean they’ve been able to profit from them. Bill has. How? Three big ways.

For starters, he leveraged his existing business. Customers were already coming into his store to look at the fashions he sold, so he had a small quantity of his specialty carriers manufactured and merely sold them right out of his store. The response was overwhelming and the belt-like carriers sold out almost immediately. Presto! A successful test marketing campaign at a low cost. Bill knew then and there that he had a winner.

Next, he repeated the process by expanding to other local retailers. He took a gamble and had another 15,000 carriers manufactured and then peddled them around to fellow store owners. Bill realized that, having succeeded on a small scale, all he needed to do was follow the same procedures and widen the territory. Other store owners—drug stores, vineyards, hair salons, smoke shops, and specialty shops—loved the carriers and sold them. The popularity of the Get Waisted encouraged him to hire half a dozen sales reps to grow his base of retail sellers. As sales grew at the grassroots level, Bill landed his first big contract: The Hudson Newspaper Group began selling the Get Waisted at major airports in Dallas and Chicago. Airline travelers loved the product.

Third, he focused on his community and listened to his customers. For example, when the new bigger smartphones came out, he redesigned the pocket so those phones could fit. “You have to be open to change and embrace it,” Bill says. “Customer tastes change, and the competition keeps trying new things. So you can’t stand still.” He also uses social media posts to point out features that make his product better than others, and he updates Facebook whenever a new style or color is added or the product is improved in any way.

These tactics have paid off. His Get Waisted products are now sold in 255 locations in more than 30 states and are used by everyone from hikers (who love it for carrying bear spray) to diabetics (who say it easily fits an insulin pump).

In the end, Bill says that his continued success will depend on paying attention to what his customers are telling him—both good and bad. “I’ve learned that if something is good, people talk, and other people find out about it,” he says. “But you have to careful. Ten happy customers may get you one more customer, but one unhappy customer will guarantee you 10 more unhappy customers.”

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