When the female counterpart is aware of the meaning of this phrase, it is usually more polite to instead say, "GYN". The female may or may not understand this abbreviation.
Super Mario: "Yeah Bill Gates, get your nut!!!!"
Luigi catches a glimpse of Mario walking into a secluded area of his back yard with an extremely attractive girl.
Luigi: "MARIO! YEAH DUDE!! GET YOUR NUT"
In this scenario, the nutshell is the female, and inside the nutshell lies the nut. As gentlemen, it is our duty to get the nut.
Guy 2: Yeah, bro
Guy 1: Get your nut!