Hey man
It is very easy if use linux, for example if script file send mail https://github.com/phalcon/forum/blob/master/scripts/send-notifications.php
In terminal you running command line
crontab -e
Then you inserting
0 23 * * * cd /root/web/.... && php send-notifications.php
here 0 and 23 correcspoding minute and hous and * running any where
# For details see man 4 crontabs
# Example of job definition:
# .---------------- minute (0 - 59)
# | .------------- hour (0 - 23)
# | | .---------- day of month (1 - 31)
# | | | .------- month (1 - 12) OR jan,feb,mar,apr ...
# | | | | .---- day of week (0 - 6) (Sunday=0 or 7) OR sun,mon,tue,wed,thu,fri,sat
# | | | | |
# * * * * * user-name command to be executed