Memories of first menstruation - whether good or bad - are unforgettable. As we have mentioned before, if you're prepared for your first period and have the requisite information about menstruation before you have your first period, you should be able to handle it without fear or embarrassment. However, if you don't know much about menstruation, your first step should be to not panic because menstruation is normal for every healthy woman.
When you get your first period, you should talk about it with your parents or any other adult that you can trust, such as an elder sister or a teacher. They will support you and provide you with necessary information and sanitary products to manage your periods.
Source: http://menstrupedia.com/articles/hygiene/first-menstruation