Paul Martino, CEO and co-founder of Aggregate Knowledge, is a four-time entrepreneur who says he always makes mistakes but that the main goal is not to keep making the same ones. Some of the lessons he shares with Vator.tv's Bambi Francisco include hiring former co-workers, getting a good advisory board and "start a big company.""It's just as hard to start a small company as it is to start a big company," says Martino, whose previous startup, Tribe Network, was acquired by Cisco Systems.Martino admits that Tribe was a good idea because it anticipated the move toward social networks, but in its earliest days the company wasn't focused properly and didn't execute well enough.