Posted in c'est ma vie , random gibberish
which they don't teach in 'Health Education'.
Hang out with your best friend frequently enough to have your menstruation cycles in line with each other's. In this case, at least both of you can go through hell together. Best friends forever!
P.S. I'm not kidding.
at first I thought you mean by synchronizing the cycle, you can have additional supply of sanitary "product" in case you run out of it...