How to make a "Favorite" system using local storage?

I'm very un-experienced using Javascript. I've searched the internet, but can't find or don't understand how to fix it.

I've a Jquery mobile based web application about party's. when the user clicked a party, they see all the info about that party.

What I want to do is make a button with "Add to Favorites" or something, and the party will be saved (using local storage) in the favorites page.