"Follow best" was a catchphrase from Standard Imperial Intelligence doctrine. It was used by Zsinj when he referred to some of his traps.
When Admiral Apwar Trigit used the term in a conversation to an undercover Face Loran—who was posing as Captain Zurel Darillian—the Imperial officer was surprised that his subordinate did not know the term. He described follow best as term that had been "practically reflex" among former Imperial Intelligence officers and should have been "second nature" to someone like Darillian.