1 Do not share your password.If you share your password the person who knows it can send messages to random people.They can send pictures to someone and post things.
2 Don't text people you don't know. If someone messages you that you don't know who is that person Don't text that person back. Then you block him for he can stop texting you.
3 Do not meet some on meet online they can kidnap you or do something else. Or ask your parents and tell a friend to come with you.
4 Block all the people people you don't know. And put your settings in were only your friends can see your profile.
5 Don't put information about you like your address. And keep your name secret and dont' give your phone number