First, strip any story (especially when it's intended to be spoken) down to the bones to the point where it's as boring as diluted broth.

Then add back a bit of context for humour or engagement.

Here's a great story: "boy meets girl, boy loses girl, they run across each other by chance and are happy together." I know it's a great story because I've heard it so many times over the years and usually enjoy it.

"So there's this computer programmer running for the train. As she gets to the platform she sees the conductor blow his whistle and board the train. But this guy jams his bag into the door and she's able to scramble in..."

Already I'm interested because there's a programmer involved, and I've just missed a train before, and I already know the plot of the story but there's a nice reversal because the protagonist is female.

But put in just a little...less is more! Then when your friends like your story they'll be inspired to tell one back.

Oh, and when I say just a little, consider Checkov's gun. You'd better fire it.