To keep your mind in focus, to not let your guard down no matter what.

To think carefully before an action, regarding the consequences that may be dangerous for you and/or others.

To stay sharp!
Alex: I'm going on holiday to London, should be awesome!

Jess: There are loads of grifters and cons, so keep your wits about you and stay out of trouble.
by hansaplast November 05, 2011
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