personality:

What and how they talk about others when they are not around.
What do they mostly talk about. Is it gossip or deep meaningful conversations?
How they treat the restaurant staff.
How they behave when they are in a position of power or authority i.e CEO, President, or even just an older sibling. Do they show ego or humbleness?
How they handle a breakup. Are they bitter or do they forgive?
What they complain about and how often they complain.
How they treat animals.
How they respond to criticism.
How they respond to praise.
Their handshake. Is it weak or firm?
How often they use the letter “I”.
How they act when they’re drunk.
How they handle rejection.
Who they hang out with mostly.
How they handle “whose fault is this?”. Is it always finger pointing or do they take ownership?
How they act in a traffic jam. Here is where you can judge how easily irritated they get.
What kind of partner they choose.
What they laugh at.
How often they take selfies.
Lastly, and most importantly, how they handle failures

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