give it the gun

big gun

A person, group, thing, or course of action that is powerful, influential, or particularly effective.

don't give up your day job

Somewhat sarcastic but usually good-natured advice used to criticise a person's degree of talent (especially in music or other performing arts), implying that they are unlikely to be successful.

eat one's gun

To commit suicide, especially by use of a firearm discharged into the victim's mouth.

fire the starting gun

To launch or trigger an event or situation.

give a damn

To be concerned about, have an interest in, to care (about something).

give a fuck

To care; to give a shit.

give a good account of oneself

To act in a creditable manner.

give a hang

give a hoot; give a damn (to care about; to place value on something)