keep a lid on

blow the lid off

To uncover (a secret or scandal).

call a lid

To inform the press that no further news will be released from a governmental body that day.

cobbler, keep to your last

One should not criticise matters outside one's field of expertise; one should mind one's business.

earn one's keep

To perform satisfactory physical labor or to provide other worthy services in return for remuneration, lodging, or other benefits; to support oneself financially.

flip one's lid

To become explosively angry, to lose one's temper.

keep a civil tongue in one's head

To maintain a polite manner of speaking.

keep a close watch

to pay careful attention to a situation or a thing, so that you can deal with any changes or problems.

keep a cool head

To keep one's cool; to stay calm.