Influencer marketing is estimated to be a two-billion dollar industry, and that number is expected to climb quickly. More than two-thirds of companies acknowledge influencer campaigns as an important part of their annual advertising budgets.

DJ and Founder of HBFIT.com Hannah Bronfman explains how she turned her Instagram feed into a business, and landed deals with companies such as Adidas and Tampax. She says it's all about authenticity.

Bronfman also shares her tips for staying true to your New Year's fitness resolutions. It takes 21 days for something to become a habit. Bronfman says more than 80% of people don't make it through those first three weeks.