Say nothin' and keep on sayin' it

phr.

Keep your mouth shut about it, and keep it shut; a wry bit of advice to stay discreet, especially about local business or a bit of scandal.

In use

Whatever ya heard about me last night down the local, say nothin' and keep on sayin' it.

Posh English

Whatever you may have heard about me last night down at the local public house, remain entirely silent, and do persist in it.