If you're doing this in html, always.
blue text"; ?>
If you're doing this in command line, it's a bit different. You'd need to create a library or find an existing one. Example: http://www.if-not-true-then-false.com/2010/php-class-for-coloring-php-command-line-cli-scripts-output-php-output-colorizing-using-bash-shell-colors/
