Regulate myself?

Grace • ❤️❤️❤️❤️❤️
I HATES that my period doesn't come on a specific date every month. Sometimes it comes on the 1st and sometimes on the 31st and everywhere inbetween then. It's a completely different date every month which always makes me uncomfortable due to the whole not-trying-to-get-pregnant category I fall under. Is there a way to regulate myself? Maybe even an herbal treatment to trigger my period? HELP. I NEVER KNOW WHEN TO BRING SANITARY PRODUCTS