Make switcher appear in Menu

I have succesfully installed the plugin and translated all my content.
Your plugin is great!!

I would like to make the language switcher appear in my navigation menu (right hand side) but have not been able to make it work.
I am using a Twenty Twelve child theme.

I searched this and other forums and already tried some code but have not been succesful.
I added the following code to my Header.php in my child theme:

<?php pll_the_languages();?>

This breaks the code. When removing the question marks ‘?’ (as read in another topic) at least it doesnt break the code but still the switcher does not appear.
Any thoughts??

https://www.ads-software.com/extend/plugins/polylang/