How to install Arrowchat completly

So I installed arrowchat, and everything went well. However I have no clue where I must place the header and footer codes specifically. It says on header.php and footer.php after the </head> tag and before the </body> tag but for one I can't seem to find it and second the footer/header editor plugins don't work either.

On the arrowchat admin page side everything is running smoothly, please anyone!