First of all, as I have been noting in this blog for some time, you have to let go of the idea of “tells” – those specific gestures that give away liars. They’re not reliable. Presumably this is bad news for poker players, too.
Second, what you should look for is a group of signals that, taken together, are a pretty good clue that the person in question is lying (unless, of course, they’ve read the article too and have taken steps accordingly). Those signals are: hand touching, touching the face, crossing arms, and leaning away.
Again, look for all of these, not individual tells. It takes a village of signs.
Here’s the really important point of this research. The more of these cues that show up in the people we talk to, the more we are inclined to think that they are untrustworthy – unconsciously. We might still like the person – but we don’t trust them. We think they’re lying.
Because most of this sort of evaluation of our fellow human beings occurs unconsciously, we have a hard time making it part of conscious thought. The conscious mind can only handle something like 40 bits of information a second, whereas the unconscious mind handles 11 million bits. So we’ve evolved to push a lot of important work down to our unconscious minds, including evaluating trust.
It’s hard work to start looking for these signs with your conscious mind, or to monitor yourself for them when you want to increase trust. But, with practice, you can increase your facility in both reading and projecting trust or its opposite consciously.
Use your powers for good.