* perldoc lib/Custom/Log.pm (or perldoc Custom::Log once
  installed) for all the usage details.

* Install using either Build.PL or Makefile.PL. They are 
  basically the same:

    % perl Build.PL
    % ./Build test
    % sudo ./Build install

         - OR -

    % perl Makefile.PL
    % make test
    % sudo make install