Summarize this article:

A period is a standard sign of puberty. There are ways of telling if your period is coming. One way of telling if your period is near is vaginal discharge. Discharge is a yellow/white substance that appears in your underwear. Once you get your discharge, your period could come within 6 months to up to 2 years time. Some girls choose to wear a pantyliner to protect their underwear from discharge. You can expect your period about two years after you get breast buds. Just after your breasts start to form, you'll probably start growing pubic hair (hair on and around your private regions).It will be soft and thin at first, but it’ll get coarser over time. Your period usually arrives around one to two years after public hair growth.

Summary:
Be aware that you can get your period anytime between ages 9 to 16. Know the signs. Note that your breasts will start to grow. Expect to see pubic hair grow.