Originating in the U.S. Army of WWII, this is the shorthand slogan to describe the hygiene preparation an enlisted soldier must do to ready himself for a military inspection by superiors.

"Shine" refers to the careful and thorough polishing of one's black military boots.

Now it has entered civilian use to mean preparation for any important social event in which one must look good, often abbreviated nowadays to just "shit, shave and shower".
Soldier 1: "We've got an inspection later today from the brass."

Soldier 2: "Guess it's time to shit, shave, shower and shine."
by david lincoln brooks February 18, 2013
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