On HubPages you create individual Hubs, and sometimes people compare each Hubber's collection of Hubs as a "blog" (of sorts). Other than that, there isn't really a way to set up a "real" blog on HubPages.
Each Hubber's profile page is a "starting point" for all of the Hubber's Hubs, and as a Hubber adds Hubs, gets fans, becomes a fan of others, or posts in the forum, his activity will begin to show up on the profile page. Adding background information or personal information to one's profile can be done by going to "edit profile".
All you have to do on HubPages is sign up for your account, add what you want to your profile, and start to write.