These days one of the most prominent buzzwords that are going around is TSCM, and this is basically an acronym that stands for technical surveillance countermeasures. For the most part these countermeasures are going to be in order to prevent you from divulging any information to third parties that you would have wanted to keep for yourself, and even though numerous people think that this is not necessary in this modern day and age it is becoming increasingly essential for people to start taking things like this as seriously as possible lest dire consequences end up arising due to inaction on your part.
Countermeasures for technical surveillance can often involve a little bit of common sense. For example, if you are truly paranoid about having your information getting leaked then you should use some kind of a signal jammer. A lot of the time bugs and the like are going to be transmitting information directly to the person listening in, which means that if you are not careful you might just end up giving these people information.
Using a signal jammer that can prevent the signal from heading out will at the very least make sure that no live transmissions can happen, although it is still definitely possible for you to get spied on regardless because there are bugs out there that often end up recording what you are saying and eventually making it so that someone can come in, take the recording and listen to it. The best part about countermeasures against surveillance is that there are a lot of them available, and many of them are worth looking into if you know the right place to get this kind of thing done.