I'm not sure if you meant to ask how to set up a blog here on Trulia, or elsewhere, or if you did intend how to step up a blog and take it to the next level.
If the former, I can tell you that setting up a blog on Trulia is very easy. Just access http://www.trulia.com/blog/post/ and start writing!
If you the latter, I recommend reading our Top 10 Blogging Tips shown at the link below. The post offers great advice to help you write content that will attract a readers and keep them interested while leveraging your unique knowledge and strengths.
Best of luck with your blog!