the act of showing class; being well behaved.
usually a term associated with parties and consuming alcohol/drugs. Teenagers often lack this ability.
These are things a person can do when "keepin' it classy"
1. Wear appropriate clothing
2. Not stumble around like a fool after consuming alcohol
3. Not hook up with random people because one consumed too much alcohol
4. not drink to the point where you

a)throw up

b)pass out

c)die (or a little less intense, get your stomach pumped)

When you eat dirt for the first time and leave your family to build a shack in the woods

When you avoid harmful substances, provocative activity, and inappropriate dress. This is exceedingly rare among teenagers, so when you find someone "keepin' it classy" congratulate them, because they can have fun without snooping to a trashy level. These people are "too school for cool" and just all around awesome people who have the most fun at parties, cause they're not worried about legal issues.

What you say when you want to look cool or attract the ladies. Also what you put on the back of your really nice truck.