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

 import XMonad.Layout.BoringWindows

Then edit your layoutHook by adding the layout modifier:

 myLayouts = boringWindows (Full ||| etc..)
 main = xmonad defaultConfig { layoutHook = myLayouts }

Then to your keybindings, add:

 , ((modMask, xK_j), focusUp)
 , ((modMask, xk_k), focusDown)

For more detailed instructions on editing the layoutHook see:

XMonad.Doc.Extending