How do I make a page "printer friendly"?

I know there is a PrintDoc snippet and I worked what I could into the coding of my site. I placed a sample button at the bottom of one page (http://www.lifewater.org/modx/index.php?id=79) with the code: <a href="[~181~]&print=[*id*]"></a>


Then on page 181, I placed the code: [[PrintDoc? &print_doc=`(this document ID)` &tpl=`print`]]

It’s not working - it links to page 181, which says print, then gives you an error that the page is not found... What code do I need to place in order for the page to show up in a printer friendly way?

What version of Modx are you using?

Most of us do it with just a separate CSS file for printing rather than a snippet:

http://www.alistapart.com/articles/goingtoprint/