You can set up a cron job or 'scheduled task' in the Scheduled Tasks section of your hosting packages control panel.
Manage Hosting -> Manage -> Scheduled Tasks
These are commands or jobs that are set to run regularly. They can be set to run at intervals of minutes, or the same time every hour, day or month.
On the Scheduled Tasks page there are three things to consider:
1. What command you are wanting to run? This is usually something like a WGET to a certain domain name or a PHP script. If you want to run a particular file such as WordPress's cron you'll need to use the correct version of PHP for the website. To select a particular version of PHP to run the command you use the commands to the right of the screen.
2. How often you need your cron to run? This is selected from the drop-down boxes under where you enter the command. You can either use the first box to run it every 5, 10, 15 minutes or you can be more specific and select particular minutes in the hour, hours in the day or days in the month for the cron to run.
3. Would you would like to have emails sent to a specified address when a cron is run? An email will only be sent if the cron produces an output so if the cron doesn't output anything no email will be sent.