It's quite easy. You don't. By definition, you can't discern anything above your own level of expertise. If you knew what an expert was talking about, there was

It's quite easy. You don't. By definition, you can't discern anything above your own level of expertise. If you knew what an expert was talking about, there was no point in consulting them in the first place. You can merely ask people you trust. Stereotypes also play an important role, even though they really shouldn't. A rather introverted, slightly socially awkward, blond guy with a ponytail wearing glasses and business casual clothing like a polo shirt while carrying a laptop with swag stickers from their last conference and a 3D printed keychain probably radiates more tech nerd energy than, say, your stereotypical school janitor.