Olivia.
G’Day.
Not sure if you have worked out how to do this, but seeing that there has not been any response to your question I thought I’d answer it.
The JOOP themeis able to draw from the Font Awesome library of icons - http://fontawesome.io/icons/
So.
1. Make sure that you have the CSS Class option enabled for your menu. This is done by selection it from the ‘Screen Options’ dropdown tab on the top righthand side of the screen.
2. Go to Font Awesome and select the icon that you want to display against a particular menu item. When you click on the selected item a new screen will appear with code.
3. Normally you would copy the “class” code, BUT, for the JOOP theme, all you need is the icon’s name. As an example, if you wanted to select say the ‘left arrow in a circle’ all you would need is the following:
fa-arrow-circle-o-left
4. This just needs to be put in the CSS Class option field.
Trust that this helps.
Cheers,
Michael.