keep up with the times

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.

fast times

A period of time characterized by quickly-paced activity, especially involving extravagant or risky conduct, sexual behavior, or other exciting events.

get with the times

To become aware of modern trends, words or ideas.

good times

Referring to a specific period of time, whether the speaker’s present circumstances or a past era recalled with nostalgia, as agreeable or enjoyable, occasionally with an ironic connotation.

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.