Wacky ex-JetBlue flight attendant Steven Slater has some advice for Thanksgiving air travelers — clean up your act!

“An elegant wardrobe paired with good manners is the hallmark of a classy traveler,” Slater told Outtraveler.com, a gay travel site. “We’re more likely to dote on refined customers than we are the T-shirt and flip-flop crowd.”

Another key rule: Be nice to the cabin crew.

“It’s amazing how many people will stare suspiciously at us before storming down the aisle in response to our smile and ‘Welcome aboard,’ ” Slater said.

He also noted that “stylish travelers” don’t rush the “gate like the stage at a Motley Crue concert.”

Slater made global headlines in August when he deployed the emergency chute on a JFK tarmac and escaped his plane with a couple of brewskies after a fight with a passenger — but lost his job.