It's biography about TAKE THAT and Robbie, I am a fan of Gary Barlow.^^

Without referring to anyone's writings etc, the correct expression is "out of my mind" not out of your brains. In this case, it can also mean, "crazy". "I am (must) out of my mind to do something stupid." "I am bored out of my mind" means that I am utterly bored.

Its a slang and what he's trying to say is that is very bored.

Are you reading Robbie Williams' autobiography????? :))))))))))))

It is difficult to distinguish formal word from slang, so I apprechiate all your answers. These are Robbie Williams' words when he was in Take That**