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

 import XMonad.Layout.Mosaic

Then edit your layoutHook by adding the Mosaic layout:

 myLayouts = mosaic 0.25 0.5 ||| Full ||| etc..
 main = xmonad defaultConfig { layoutHook = myLayouts }

For more detailed instructions on editing the layoutHook see:

XMonad.Doc.Extending#Editing_the_layout_hook

In the key-bindings, do something like:

   , ((controlMask .|. modMask x .|. shiftMask, xK_h), withFocused (sendMessage . tallWindow))
   , ((controlMask .|. modMask x .|. shiftMask, xK_l), withFocused (sendMessage . wideWindow))
   , ((modMask x .|. shiftMask, xK_h     ), withFocused (sendMessage . shrinkWindow))
   , ((modMask x .|. shiftMask, xK_l     ), withFocused (sendMessage . expandWindow))
   , ((modMask x .|. shiftMask, xK_s     ), withFocused (sendMessage . squareWindow))
   , ((modMask x .|. shiftMask, xK_o     ), withFocused (sendMessage . myclearWindow))
   , ((controlMask .|. modMask x .|. shiftMask, xK_o     ), withFocused (sendMessage . flexibleWindow))

For detailed instruction on editing the key binding see:

XMonad.Doc.Extending#Editing_key_bindings.