Formidable pro – contact form – accordion

Hi guys
Hoping you can help
I’m having issues with the formidable form, specifically adding in an accordion to section headers so only 1 question at a time shows. I’m using this help but I think it’s out of date
http://formidablepro.com/help-desk/turn-your-collapsible-sections-into-an-accordion/
Just wondering if there’s something massive I’m missing or if it’s a very simple tweak I need to do.
Can anyone help or help me find a way to sort it?
Much appreciated
Rachael