Staying safe on Facebook Follow these simple steps!
Click on the padlock icon at the top of the screen
One of the options that will be shown is "Who can see my stuff?". You should change this to friends and make it your responsibility to ensure that your friends are only people you know, so these are the only people who can see your posts.
Another option that you will be faced with is "Who can contact me?". Here you can set who is able to message you and who can send you friend requests. The best options are "strict filtering" and "friends of friends".
Finally there will be a section that says "How do I stop someone from bothering me?". This is where you can block a user if they are harming you in any way. It is a great thing to block someone to stop cyber bullying from continuing.