The only way that I can think is if we use the Sopranos as an example, if I was Tony the only guy I would trust would be Silvio, basically I would only ever issue orders through him. I would only talk generally with other members, not about mob business. I don't think you should ever talk inside nowadays, talk in parks, wide open spaces away from possible listening devices.
Chin had a good idea by never allowing people to use his name, also putting a dummy boss like Salerno was a good plan.