Suppose after you set up your blog you decide you don't like the blog name anymore and you want to change it.

From your Dashboard, go to Settings and click on General.

At the top of the General screen, you will see the Site Title field.

You can now change the Site Title to anything you want the blog to be called. The Tagline is a subtitle, or extension of the Site Title, where you can include a brief description of what the blog is about.

When you are done, remember to click on Save Changes to update your blog with the new site name.