At first, I would like to welcome you to HB, I am sure you will enjoy here, it is a great community.
Answering your question, does not mean that I consider my self as a successful hubber, but I believe that I am on the way to success.
It is very important to write a quality hubs (well searched & rich of information, nicely arranged) about a topic you like (Tech tips and tricks, Blogger tips), people will know that you have knowledge & will trust you more. I read also that building a niche could boost SEO.
You have to link your hubs related to same topic to each other, this helps.
Note: I have a wide variety of hubs, this is wrong.
Now, you have a mission to purplish 5 featured hubs to start the success way.
Hope, it helps.