apps \ metacity \ general
On the right hand side of the screen you should see an option called button_layout.
This option takes a string value separated by commas, as well as a
colon that separates which side of the window the buttons will be on.
To mimic the OS X setting, enter this string:
close,maximize,minimize:menu
In this example, the close/maximize/minimize buttons are on the
left, and the menu button is on the right. You can remove an item from
this list if you’d like. For example, I don’t really use the menu
button so I usually just remove it.
or 