Near the top right of your timeline, is a small down-arrow. Click it, select "settings". One of the settings available is "privacy settings." Set it so that everything you want to be private is set to "only me" (or specified people.)
Have a look at
Facecrooks.com | How to Avoid a Facebook Scam | All about Facebook Scams . Lots of info, tips and tricks, warnings of scams. You could consider that site a privacy advocate.
I find that having everything set to "friends only" a pretty good compromise. And just refrain from posting anything at all that could later come back and bite you in the arse.