A growing number of companies are turning their attention to search engine optimization (SEO) as a way to increase traffic to their site in the hope of building sales. And for one online shirt company, SEO is one of the primary ways it’s getting its name out there.

ShirtsMyWay launched its site earlier this year and says by giving users the ability to design their own shirts, it has 7 trillion shirts available for sale. Company co-founders Peter Crawfurd and Michael Yang told Econsultancy that since the February launch, it has sold thousands of shirts to more than 20 countries around the world with the majority of its traffic coming organically.

"At this point in time we have not had any marketing budget really," the two co-founders told the website. "Most of exposure is through word of mouth, PR, and SEO"

For companies selling clothing and accessories, it seems that search engine optimization (SEO) might be one of the best ways to market.

Hat Retailer, an online and brick-and-mortar hat vendor, recently announced that the use of online marketing techniques like search engine optimization (SEO) had helped the site increase traffic by 175 percent over the last year.