What it means for a guy: This is important, so pay close attention. IT TAKES TWO PEOPLE TO MAKE A BABY. That means you and your partner are responsible for ensuring you are covered if you want to have consensual sex and do not want to make another human being while doing so. If you do not know whether your partner is using a contraceptive, ask her. If her answer is NO and you do NOT want to have a child together, use a condom or DO NOT HAVE SEX. Don't forget, babies are made by having unprotected sex. We can't stress this part enough.
*Special fun sex tip: To protect yourself from STDs while still having intercourse, use a condom. All other contraceptives listed here do not prevent or cure STDS.
And that's it. The miracle of life, in one adorable listicle. The No. 1 thing to remember is that periods are unique and different for each female, and her reproductive system belongs to her and her alone. It is your job to respect the women in your life, respect their bodies, and never, ever, ever, ever blame their feelings on PMS.