Customizing Top Menu Bar for Forum Groupings

[Truth66]

I'm new here so my appologies if this has already been raised.

I'm trying to customize my site to have Groupings of Forums accessed by the main Menu at the Top.
An example of this is located here:

http://allnurses.com/

As you can see the Top menu has more than the basic 4 tabs.

What I want is: Home Tab, Second Tab, Third Tab, Forums, Blogs, What's New

The second Tab I want linked to a specific Parent Group of Forums
The third Tab linked to a specific group of Parent Group of Forums
The fourth tab linked to a specific group of Parent Group of Forums

The User Groups would still have access to all of the forums. I just want these extra tabs to make things easier for navigation for my users, as opposed to having everything under one tab.

How do I add these additional tabs and create the links to the specific Parent Forums?

My appologies, my html knowledge is really limited.

Thanks Again