Oversharing
There's nothing more solidifying of a person's character and self than finding out something really cool or impressive about them some distance into your friendship.
I didn't know you went to Harvard!
You seriously go to the gym every morning at 6AM?
Your dad invented Post-Its!?
Less is more. Everything comes up eventually, and waiting for that makes sense. An organic moment to share that you were basically an equestrian prodigy will not kill you; really, I don't need to hear about it five minutes into our first conversation. A little bit of mystery goes a long way.
[Photo via @carolinevreeland]