To delete this default post just go to the dashboard and you will see a column named ‘Your stuff’. If your blog only has the “Hello world” post you should only see three things there; that post, the default comment and the default ‘about’ page.

Next to the “New post: Hello world!” you’ll see a link that says ‘edit’. Click on it. When taken to that page scroll until the end and under a bar named trackbacks you’ll see a button that says delete. Click it and you’re done!