1. Drag the Rakudo_Star folder onto the Applications folder.
2. In a Terminal window, type this command:
    alias p6='/Applications/Rakudo_Star/bin/perl6'
        ( This step only affects this one window; to make available to all
          future sessions, add the line to your ~/.bash_profile file. )

You can now run a Perl 6 program like this:
    p6 filename
or run code directly from the command-line with the -e option:
    p6 -e 'your code here'

Try this:
    p6 -e 'say "Hello, world!";'

You can always skip the alias and use the full path:
    /Applications/Rakudo_Star/bin/perl6 -e 'say "Hello, world!";'
or alternately, add Rakudo Star to your path:
    PATH=$PATH:/Applications/Rakudo_Star/bin
    perl6 -e 'say "Hello, world!";'

See also README in /Applications/Rakudo_Star/docs/rakudo/README .