If you just want to get started quickly, here is a crontab entry that will run cron once every hour at ten minutes after the hour:
- 10 * * * * /usr/bin/env PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin COLUMNS=72 cd [DOCROOT] && ../vendor/bin/drush --uri=your.drupalsite.org --quiet cron
+ 10 * * * * cd [DOCROOT] && /usr/bin/env PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin COLUMNS=72 ../vendor/bin/drush --uri=your.drupalsite.org --quiet cron
You should set up crontab to run your cron tasks as the same user that runs the web server; for example, if you run your web server as the user www-data: