Cron Jobs are linux commands which allow you to schedule a task to be performed automatically and periodically.
Please find below the steps required to achieve the set up of your custom cron jobs.
1) Login to cPanel
2) At the bottom, in the Advanced section, click on the Cron Jobs icon
3) At the middle of the fold, you'll notice a field where you can set up an email address where a notification will be send for each task completed.
4) Then, you'll have the schedule functions which allow you to set the timing for the command to be executed. You are able to set predefined settings such as once a day, once an hour..
5) In the Command field you would need to type the following :
php -q /home/"yourcpanelusername"/public_html/path_to_your_file
For instance :
php -q /home/besthost/public_html/folder/mycronjob.php
That's it. Once you cron job is set up, it will be triggered for each period you have defined.