Online Privacy and Security
Always make your password something long and difficult to guess.
Don't Get Scammed!
Always make sure you know the page is legitimate. Don't open up links or emails from unknown sources.
Keep Your Privacy
Only put out what you're sure won't hurt your reputation. Also make sure your finances aren't somewhere where they can do damage. ex: Don't give a random website your bank account or card number.
Always make sure you check user agreements to see if there's any hidden messages that may cause inconvenience to you later.
To prevent any accusation of copyright infringement always check pictures and search options to be sure the photo is for public use.