Is that a picture of your setup, or are you just using it as an example?
If it's your picture, you've already got tabs (Main, Customizing, Graphics, etc..).
If it's not your picture, and you're asking how to do it... right-click on your dock, and select "dock settings". In the window that opens, select "manage my docks". Then, select "create new tabbed dock".
Hope this helps.
