There are many varied ways to promote your hubs, The trick is to use as many as possible and use the methods that work for you.
A cool process is to have other people promote your hubs. Get others, via any social networking sites you can, Facebook, Twitter, Reddit, StumbleUpon, etc to talk about your hubs. Ask your friends to repost, share, like, and whatever else they can do to increase your exposure.
If you really want to promote a hub, consider paid promotion methods, such as fiverr.com. Sounds a little counter-intuitive to pay for promotions, but if you wrote a good hub, did good keyword research and SEO, then investing a few dollars to get several hundred people bookmarking your hub can be a considerable boost to your hub rankings.