Create a file:

/etc/systemd/system/schedule-mysite.service

Add the following content:

[Unit]
Description=Runs and keeps alive the artisan schedule:run process for www.mysite.com

[Service]
Restart=always
WorkingDirectory=/var/www/www.mysite.com
ExecStart=/usr/bin/php artisan schedule:work --env=production
StandardOutput=append:/var/www/www.mysite.com/storage/logs/schedule.log
StandardError=append:/var/www/www.mysite.com/storage/logs/schedule.log

[Install]
WantedBy=default.target

To enable it:

$ systemctl enable schedule-mysite

To start it:

$ systemctl start schedule-mysite

To get the status:

$ systemctl status schedule-mysite