Fix typo on readme

README.md

@@ -33,7 +33,9 @@ Harmony is a responsive jekyll theme.
 3. If you completely new to jekyll, please read more about [Jekyll](http://jekyllrb.com/) and [Github pages](https://help.github.com/articles/using-jekyll-with-pages).
 4. Change your directory into cloned repository. 
 5. Run `bundle install`
-6. Run the jekyll server by having: `jekyll serve --baseurl ''` or `rake preview`   
+6. Edit the _config.yml on root directory. Change `url` property to to 
+`http://127.0.0.1:4000` since you are going to run on localhost.
+7. Run the jekyll server by having: `jekyll serve --baseurl ''` or `rake preview`   
 
 Try to locate your browser at [http://localhost:4000](http://localhost:4000).