How do I print something out in color?

In general, you don't, because you don't know whether the recipient has
a color-aware display device. If you know that they have an ANSI
terminal that understands color, you can use the "Term::ANSIColor"
module from CPAN:

use Term::ANSIColor;
print color("red"), "Stop!\n", color("reset");
print color("green"), "Go!\n", color("reset");

Or like this:

use Term::ANSIColor qw(:constants);
print RED, "Stop!\n", RESET;
print GREEN, "Go!\n", RESET;