You can use this module with the following in your ~/.xmonad/xmonad.hs:

 import XMonad.Layout.TabBarDecoration

Then edit your layoutHook by adding the layout you want:

 main = xmonad defaultConfig { layoutHook = simpleTabBar $ layoutHook defaultConfig}

For more detailed instructions on editing the layoutHook see:

XMonad.Doc.Extending

tabBar will give you the possibility of setting a custom shrinker and a custom theme.

The deafult theme can be dynamically change with the xmonad theme selector. See XMonad.Prompt.Theme. For more themse, look at XMonad.Util.Themes