The easiest way to add more of the expanding and collapsing content blocks is to simply copy and paste the existing content items. There are two items you'll need to make sure you have: the heading and the main content.
The heading item has the according-heading CSS wrapper class and the main content has the accordion-text CSS class. Make sure you paste the text DIRECTLY BELOW the appropriate heading, like so:
Once you've pasted both items, all you need to do is click into them and edit the HTML Content as desired.