Write relevant articles covering a sub topic of your hub and include a link back to your hub. Submit as many of these original articles to high ranking article sites such as Ezines, GoArticles and Amazines.
Then bookmark these articles on a few of the top social bookmarking sites.
Also submit your RSS URL to sites such as Zimbio,where once submitted your new hubs will show up on their site automatically and they will then categorize it for you or you can do that yourself.
It takes time and it does depend on the targeted keywords you have chosen.