The following screencast shows how we can set up a section having 3 posts, then another section having some content, and another section having the next set of 3 posts that are offset by 3.
Code for manual query string entered in the third section:
post_type=post&posts_per_page=3&offset=3&no_found_rows=true
Comments
Provide a URL of your site/webpage if something is not working.