Many politicians wear religion 'on their sleeves'. [=show their religious beliefs in a very open way]
The mayor's critics were 'laughing up their sleeves' when news of the scandal was first reported.
He 'wears his emotions/heart on his sleeve'. [=his emotions are easy to see]
(..) His parents didn't give him enough attention. Uh, Detective... We're looking for three white males, one of whom has sleeve tats on both arms. And how do you know that? I had an informant on the inside. He's been here for years. (..)2013 TvShow: Brooklyn Nine-Nine Title: Pilot Season: 1 Episode 1