The word "cool" has become so popular that anyone or anything that is considered good is branded as "cool". One is uncool when one does not go with the flow, when one goes against the norm or when one offends others. You are cool when you do not experience any of the following:
1. Nervousness in front of other people. Being calm or not showing your real feelings can make you cool during nerve-wracking situations.
2. Anger is very uncool, especially when you blow off steam in front of others, that is so uncool. The person you berate may look good on those who witness your outburst and you will come out as the devil's advocate. Avoid this. Be cool even during rough times.
3. Love what you have and who you are. Flaunt what you got. That's cool.
4. Whining or complaining seldom changes things. Just give your best and stop whining.
5. Being uncooperative or apathetic is uncool. You are a part of this universe of humans, so act like you are one. Be helpful.