Since the early days of social, Stephanie Cartin has been at the forefront of this new media, which prompted her to start the Socialfly social-first digital and influencer marketing agency based in New York City. Socialfly has today 30 full-time employees and has been named to Inc. 5000's fastest growing private companies two years in a row.

I met Stephanie through Entreprenista League, which she co-founded with Courtney Spritzer and is a warm and welcoming community for women founders. She is also a co-host of the podcast and co-author of the book "Like, Love, Follow: The Entreprenista's Guide to Using Social Media To Grow Your Business." 

But wait, there's more; she also co-founded Markid, a marketplace for parents to buy and sell baby and kids' new and gently used items. In addition, she is currently building a new business helping early-stage founders collaborate with influencers.