Following Three Security Options makes your Facebook Account Secure and Hack Proof.
1) You can enable Login Notification so that whenever any body (or a hacker) tries to login with your User ID and Password, you will receive a Notification on your cell phone and you will come to know that it's time to change your password right now because the hacker has got your password and is trying to log in to your Facebook Account.
To Enable Login Nofication
Go to Home -> Account Settings -> Security -> Login Notification. Put a Check Mark on your preffered option and
click Save Changes button.
2) Always check your Active Sessions. If you notice any unfamiliar location or device, it means your Facebook Account is at risk. Just click on End Activity and dont forget to change your password after that.
To Check Active Sessions
Go to Home -> Account Settings -> Security -> Active Sessions.
3) Enable Secure Browsing to make your account more secure.
Go to Home-> Account Settings -> Security -> Secure Browsing.
Know more https://web.facebook.com/about/basics