Justin Bieber has a coach who teaches him "how to flirt".

The 16-year-old 'Baby' singer reportedly has an advisor called Ryan who tells him how to act in order to impress the public and how to present himself to members of the opposite sex.

A source told Lifeandstyle.com: "Ryan shows him how to walk, how to talk, how to flirt, even how to wear his hat to attract as many girls as possible."

Justin - who is regularly mobbed by screaming fans when he appears in public - has previously admitted he doesn't understand why he is so popular and doesn't see himself as "cool".

He said: "I'm not even that cool, like seriously. What is so cool like that you freak out? These girls crying, it's like I can't believe that, I'm so honored that you're crying but, I don't know, it's crazy to me!"

When the singer is flirting with girls he can, however, be sure of their scent - as he is planning to release his own perfume.

He said: "Most male celebrities do male colognes for other males. I think that me making a female fragrance is just a different idea and I think it's going to be successful. It's going to be really big."

Justin's autobiography 'First Step 2 Forever' is available now.