You need to put all your commands into a file (script), store that somewhere accessible (I use /etc/Jobs, but eg /etc/scripts would be fine.).
Then put the full path to your script there as command. ( eg /etc/scripts/mailingscript.sh ).
The script file needs to be executable for root!
Using advanced options in Cron, you need 5 tokens in the “Time of the job” field.
eg: "0 6 * * * "
That would work!
My 2 cents
Andy