First when you start, there will be not much followers. So what you need to do is to bring in active traffic. By means of social networking like posting, sharing in Facebook for example. Email to your friends, relatives and colleagues. This will increase the traffic but you need activity doing it.
In long run, you should optimize your hub for SEO. In this way, Google will rank you high and you will get automatic traffic from Google.
Always remember, create valuable and quality hubs.