know which end is up

From the common marking this end up on parcels to guide proper transport.

• "He was too stoned to know which end was up."
• "He's so in love, he doesn't know which end is up."
• "“I'll gladly take criticism from a cop who knows which end is up and isn't afraid to do the job the way it should be done.”"
• "“I'm not some naïve, virginal little nothing who doesn't know which end is up.”"
• "“[B]elieve me, she is some catch for the right boy—for a boy which knows which end is up.”"
• "“When someone doesn't know which end is up, who knows why they do things.”"
• "The whole company is in disarray! Nobody knows which end is up."

• know which way is up

• know one's way around
• know which side one's bread is buttered on