One of the best way for business people and professionals to differentiate from competition is to get published in local, regional, or even national publications. Because writing about topics relevant to one's business or profession confers an aura of expertise, more people should seek opportunities to contribute articles to publications.
In addition to writing articles yourself, you can do great service to other business people if you uncover opportunities for them to write for local publications. If you discover a publication that is seeking contributions in someone's field let them know about it.
If you use this marketing technique yourself, ask the editors what other subjects they are seeking articles about. You might even pre-pitch your friends or contacts and suggest articles they might contribute that would be in alignment with the publication's mission or market.
By helping your friends market, you build your relationship, it's as simple as that.