I'm glad you selected that one. It's the easiest to implement.
Go to Dashboard > PageLines > Site Options > Website Setup. Scroll to the very bottom of the screen.
You'll see Sidebar Wrap Widgets. In the drop down box, select On Bottom of Sidebar. Save the settings.
Scroll up and click the Layout Editor.
Set up your layout with two sidebars left.
Set the width of each of the main sidebars. Save.
Now go to Dashboard > PageLines > Drag & Drop. Click on the Wrap and drag one of the sections there. I use Tertiary Sidebar, which should do the trick for you too.
Your site should have the layout on the left of my image now and you should be all set to go.