Jenny Langbehn’s dog, Carlito, is a diminutive Chihuahua mix with an outsized attitude.

“He went after a nun once,” Langbehn confessed. “That was hugely embarrassing.”

And roving bands of schoolchildren are at risk when Carlito is out for his daily strolls.

But sing some Italian opera or tease him with a worn pink sock, and Carlito transforms into a kinder, gentler creature.

“You have to know your dog,” said Langbehn, author of a book that teaches people how to have a howling good time with their canine companions.

Among the “97 Ways To Make A Dog Smile” (Workman Publishing, $7.95), are special rubs, pats, massages, scratches and games, from Go Speed Racer to The Thumper, that Langbehn has practiced on dogs she has come to know both personally and professionally.

Langbehn, 28, is a veterinary nurse and resident “dog smiler” at a clinic in Manhattan.

“I have had a manageable number of animals all my life,” she said. “Lost kittens, stray dogs,” even a dusky-headed conure named Bird that inexplicably screeched “cream of wheat” again and again.

Through trial and error, at home and at work, Langbehn learned the best ways to successfully divert animals from things unpleasant, to calm them, to make them jump for joy. “The fun in the book is finding the little things that your particular dog best responds to,” she said.

It might be Tickle the Ivories, in which the pet owner plays her dog’s ribs like a piano keyboard while singing a tune. Or Peanut Butter Swirl, which involves smearing a small amount of peanut butter on the dog’s tail and watching her spin like a top. Or Flying Saucers, in which the dog owner hurls miniature rice cakes for Fido to catch and eat.

“Most of these require that you be a little bit goofy,” Langbehn said.

Her own surly pooch, Carlito, despises foot rubs but adores sock games and makeshift opera songs that feature his name. “My Italian is decent, but I don’t know all of the words to all of the songs,” Langbehn said. “So I substitute his name for the unknown words. He loves it!”