There’s long been an adage that, to catch a thief, one must think like a thief. Therefore, ironically, former burglars are probably some of the best imaginable sources of information on how to keep your home safe and prevent it from being burgled.

Since they’ve broken into homes before, people like them know exactly what sorts of weaknesses and security holes to look for. And by learning from them and taking their advice, you can actually do quite a bit to keep your home, family, and belongings safe.

Here are a few important security tips brought to you from the mouths and minds of former burglars.

1. Watch What You Post on Social Media, and Keep It Private

The more information you post on your social media accounts about your personal life, the more that people can find out about you. It may seem incredible to have to say this in our social-media-saturated age, but you really shouldn’t post anything on the internet that you aren’t comfortable having the public know about you. It only bears repeating because so many people still fail to heed this advice.

Criminals can use any kind of information you post on social media to target you. They might find out where you live and work or what your phone number is. If you post about when you are at work, on vacation, or otherwise away from home, burglars can use that to strike when you aren’t there to stop them.

The best policy is to either not post such information or make sure that it is only visible to those you trust if you do.

2. Be Careful Whom You Trust

Some burglars have taken extremely sneaky and underhanded steps to discover the layout of a home before deciding to target it. It’s not unusual for them to impersonate UPS or FedEx delivery men and ask to be invited into your house, for example. As a general rule, you shouldn’t let someone into your home unless you know them personally.

3. Invest in a Guard Dog

Placing all kinds of deterrents around your home is an excellent idea. One of these is a big, scary guard dog. If you can, get a large dog like a Rottweiler to stand guard over your house. That will put yet another major obstacle in any would-be burglar’s path, which would make one less likely to target your house at all.

4. Keep Your Keys Far From the Door

Even though it might be convenient to do so, it’s a very bad idea to leave your house keys anywhere near any of the doors of your home. A crafty thief might be able to shove a device through the mail slot and retrieve them. Don’t expose yourself to that risk.

5. Put Cameras Around Your Home

The More cameras you have around your home, the more likely you are to catch any possible burglars in the act. And the more suspicious burglars become about being watched, the more likely they will flee. A security system that includes not only cameras but alarms and an automatic function to call the police is even better. Even those criminals who are not scared off by cameras will be more easily caught if you have them on video.