Retroactively, you can privatize your Facebook profile by visiting the Limit Past Posts link and clicking the Limit Old Posts button to ensure that all the content you've already shared becomes private to your friends only. One caveat, though: If you ever tag anyone in a Facebook update, your tagged content will show up on that person's Timeline, and thus will be exposed according to their personal privacy settings.
Lock down your Timeline: Finally, take a moment to safeguard against the threat of embarrassing photos or video popping up in your Timeline without your knowledge by fine-tuning Facebook's Timeline Review.
Go to the Timeline and Tagging Settings menu (if you're still in the Privacy Settings menu, you can find the other settings menus on the left side of the screen). Now that you're reviewing your Timeline Settings, scroll down and turn the option titled 'Review posts friends tag you in before they appear on your timeline' to On.
The three simple changes described above will go a long way toward improving your Facebook privacy, but a bunch of other potentially useful privacy settings are scattered throughout Facebook's Account Settings menus. Take the time to read through them. Facebook is one of the biggest social networks on the planet, and knowing how to control your information is the best way to control how the world views you.
Tidy up Twitter
Because Twitter is a bare-bones communication service for exchanging photos, videos, and short text messages, it doesn't give you many opportunities to share private data inadvertently. But although you remain responsible for the lion's share of the data in your feed, Twitter still has a few potential privacy leaks that you can quickly plug.
Don't link Twitter to Facebook: First, you should probably unlink your Twitter account from Facebook and any other social networks. Not only is it risky to have your Twitter username popping up in your Facebook timeline--and thus being associated with real-world Facebook information such as your name, location, or employment history--it's also really annoying for your Facebook friends.
Unless you're a small-business owner or a minor celebrity trying to spread information across multiple social networks at once, keep your Twitter account separate from your other social media platforms. Simply log in to Twitter, click the gray gear icon in the top-right corner of the screen, and make your way to the Profile section of the Settings menu. Scroll down to the Facebook section, and you'll see the option to disconnect your Facebook account from Twitter for good.
Turn off geotagging: Second, turn off Twitter's geotagging system to ensure that you aren't including your location in every update. Sure, it's a neat feature, but at best it merely affords you a geographical record of where you've tweeted. At worst, geotagging creates a public record of your physical location in real time, making it easy for malefactors to track your movements and use that data for evil.
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