When running this daemon, you must disable the cron job that calls the "send-campaigns" command, this is very important since if both running you'll get in trouble.
From the article:Do I run this everytime before I run a campaign?
After you have tested this feature and you see it working, you can create a cron job for this daemon to run once at 10 minutes.
First time when it will run, it will start the daemon, next time it will check to see if the daemon runs and if it does, it will do nothing. If it doesn't, then it will start it again.
The cron job you'll have to add must look like:
*/10 * * * * /path/to/mailwizz/apps/console/commands/shell/send-parallel-campaigns > /dev/null 2>&1