have calluses from patting own back

(redirected from break arm patting oneself on the back)

have calluses from patting one's own back

 and break one's arm patting oneself on the back
Fig. to be a braggart. If you haven't heard about Bill's latest achievement, he'd be glad to tell you. He has calluses from patting his own back. Jane: I did a really wonderful job, if I do say so myself. Tom: If you're not careful, you'll break your arm patting yourself on the back.
See also: back, have, own, pat