Oscars speeches: The secret to the perfect acceptance speech

— -- While winning an Oscar is the best part about the Academy Awards for the stars, for the people watching at home, the speeches can either make or break the night.

For example, everyone fondly remembers Cuba Gooding Jr.'s lively 1997 Oscars speech after he won best supporting actor for his portrayal of fictional football player Rod Tidwell in "Jerry Maguire." But it's hard not to cringe when looking back at Angelina Jolie's 2000 acceptance speech -- which she began by declaring, "I'm so in love with my brother right now" -- after she picked up best supporting actress for "Girl Interrupted."

A great Oscars speech is an art in itself. And when all eyes are on the winner, some rise to the occasion, while others crack under the pressure.

According to the late Gil Cates, the key to a stellar Oscars speech is all in the delivery.

"I think the best acceptance speech has a lot of emotion to it," Cates, who was a producer of the awards show, said in a March 2010 interview on ABC's "World News Now."

Cates also noted that it is preferable for the award winner to have "thought about what they're going to say beforehand," and not ramble on with a bunch of filler words such as "um" and "uh."

The number one Oscars speech no-no? Reading from a script.

"The cardinal sin is whipping out a piece of paper," Gates said. "As soon as someone whips out a piece of paper, you're dead."

The Academy Awards air this Sunday at 8:30 p.m. ET on ABC.