How to have "Category" tabs under Portfolio

Hey guys,

First of all, shout out to One Designs for releasing such an awesome theme to the public.

Anyways, this may be a simple fix but I have honestly exhausted my trial and error methods and cannot seem to find the solution to this. On the pinboard theme demo, if you navigate to “Portfolio”, there are different category tabs just above the portfolio pictures. They are labeled “Abstract” “Animals” “Instants” etc…..

Here is the link to what I am talking about: http://demo.onedesigns.com/pinboard/?page_id=6

What do I have to do to my posts in order to have these tabs displayed and how do I set up the Portfolio page to allow this?

Any comments or suggestions would be extremely appreciate it since I have spent hours trying to figure this out!

Thanks!