A real good tip if you are new to using the gui-editor is to press F1 and read through that little page. Also its always good to save your finished GUI to a file and store that somewhere safe in case you need to add more elements later on.
This is how my recently saved GUI looks like in code.
$[
1.063,
["AdminMenuGUI",[[0,0,1,1],0.025,0.04,"GUI_GRID"],0,0,0],
[2203,"background-inv",[1,"",["0.566952 * safezoneW + safezoneX","0.225 * safezoneH + safezoneY","0.144205 * safezoneW","0.418 * safezoneH"],[-1,-1,-1,-1],[-1,-1,-1,-1],[-1,-1,-1,-1],"","-1"],[]],
[2200,"menubackground",[1,"",["0.572102 * safezoneW + safezoneX","0.324 * safezoneH + safezoneY","0.133905 * safezoneW","0.308 * safezoneH"],[-1,-1,-1,-1],[-1,-1,-1,-1],[-1,-1,-1,-1],"","-1"],[]],
[2201,"headerBackground",[1,"",["0.572102 * safezoneW + safezoneX","0.258 * safezoneH + safezoneY","0.133905 * safezoneW","0.066 * safezoneH"],[-1,-1,-1,-1],[-1,-1,-1,-1],[-1,-1,-1,-1],"","-1"],[]],
[1100,"headerText",[1,"",["0.577253 * safezoneW + safezoneX","0.269 * safezoneH + safezoneY","0.123604 * safezoneW","0.044 * safezoneH"],[-1,-1,-1,-1],[-1,-1,-1,-1],[-1,-1,-1,-1],"","-1"],[]]
]
If i copy this to the clipboard i only need to open up the GUI editor to have the gui show up again. Real handy when you need to edit or add!