Hans Christian with the state of web printing. All the old classics are still important, like
display: none; on irrelevant stuff (like navigation) and using pseudo elements to display the URL's of links. But there are new kids on the block like
@page which helps you style individual printed pages and control printing orientation for certain elements,
-webkit-print-color-adjust: exact; for printing background colors/images, printing crop marks, and preventing widows.