Drupal CRON Setup and Scheduling - cron.php

From the command line, open the crontab using the default editor. You can change your default editor, just google the commands.

crontab -e

And then add the line:

30 23 * * * php /home/account/public_html/cron.php

This will run cron.php at 11:30 every day. For more configuration settings, see the drupal page or this good tutorial.