It's probably the wrong way to do it, but technically you can copy files by hand into /usr/lib/perlx/site_perl/5.x.x/. That location could be wrong on your machine, try perl -e 'print "@INC\n"' for a list of possible default locations.

Arguably, the correct way to do it is to look at Module::Build or ExtUtils::MakeMaker (oldschool but still my favorite of the two) and then mostly ignore those documents by using h2xs — which helps you use the current best practices (by default).