Be a good digital citizen
Keep in mind that anything that you put up will stay there for the rest of your life. Even if you delete it, if someone wants to, they can get it back. So think hard wether you want everyone to be able to see what you are posting.
One of the best ways to avoid causing embarrassment or harm to your friends and family is to always ask permission before posting pictures of them in social networking sights. You never know who's looking and what they will do with the image.
If you pirate you don't gain.