If I had ever learnt, I should have been a great proficient.

He thinks the sun comes up just to hear him crow.

A session of boasting won't attract any real friends.  It will set you up on a pedestal, however, making you a clearer target.

What do the Texans say? All hat, no cattle.

I'm not sayin' she's a bragger, but if you've been to Paradise, she's got a season ticket.

I cannot speak well enough to be unintelligible.