Who said "The key to the whole thing is to sound confident."?

This quote is attributed to George Costanza.

The key to the whole thing is to sound confident. - George Costanza

"The key to the whole thing is to sound confident."

George Costanza Success

"I'm out there Jerry, and I'm lovin' every minute of it."

"These pretzels are making me thirsty."

"Master of my domain."

"It's not a lie if you believe it."

"Success comes to those who never give up."

"Success is measured by happiness, not money."

"You make your own luck in this world."

"You have to be organized to be successful in anything."