You can choose from a variety of column layouts.
If you select a layout with more columns than your current layout, one or more columns will be empty. You can drag and drop content into the empty columns.
Tip: If your layout choice creates a tab that requires horizontal scrolling, maximize the browser window. It might also help to reduce the banner and Web search box through Change Appearance > Searchbox Size. If these don't work, then you might want to try a different column layout.