Page Navigation Blocks

hi....This is giving me problems...
there says "To make this work
you need to change the current coding in each template, to the below coding:"

and then some "~ pagenav: <!--Pages ($totalpages): --><b>$firstlink $prevlink $pagenav $nextlink $lastlink</b>"
what this mean?? where do i put this?? which template?? and which line?? it gets me confuse.