I will stranger-protect my MySpace profile.
It only takes a second to stop giving access out to the whole world and only allow your friends into your online neighborhood by adjusting the private/public settings. While it doesn’t prevent you from being friends and commenting in the public space, it does stop onlookers from getting to see all of you. People can still see your profile image and contact you, but this simple step makes it easy to put a big roadblock in the way of the bad guys. Once that’s in place, just make sure you be careful who you add as friends because they get access to everything.

I will limit the use of personal information online.
Encourage your students to use only their first name when talking to others—and the old rule “don’t talk to strangers” is very real in this world. Limit the use of pictures, fun and energetic is the rule here, not lurid or suggestive. And most importantly be careful not to post revealing routines, patterns or places. Less is almost always more, and sometimes it’s better to post about what happened instead of where you’re headed. And finally, remember that what you post is like a billboard alongside the highway, a giant flashing billboard along the information superhighway. Every person passing by can see everything you put up there.