IMPORTANT.
Fidgeting
Might seem obvious, but most people aren't aware enough to recognize their own nervous habits and then consciously fight to conceal them.
Source: intrepidgirlblogger / via: forbes.com
Sweating
Yes, we know, this feels like it's out of a bad mob movie, but it's still one of most common signs of raised stress levels.
Source: fatsoullife / via: forbes.com
Failure To Make Eye Contact
A very common indicator of deceit or guilt.
Source: hayy-dee / via: forbes.com
Dilated Pupils
And it they can manage to look you in the eye, check for this sign of high stress levels.
Source: intrepidgirlblogger / via: forbes.com