Create Categories on Top

Hey Everyone

Please tell me how I can create my categories through tabs on the top of my website, instead the sidebar. I tried doing it through creating menus however, my theme only allows one menu.

This is my website- http://blurrtube.com/

The orange large bar, I would like my tabs to all be there with different categories that viewers may click on.

Please tell me how I can do this.

Thank you in advance.