Trust the Plan.

The men from Massachusetts, Connecticut, and New Hampshire were ordered to hold their fire until the enemy drew so close that their musket fire would have its most devastating effect. It was at this time, legend claims, that one of the commanding officers from the colonies ordered: "Don't fire until you see the whites of their eyes!"

"Don’t throw away a single shot, my brave fellows; . . . don’t throw away a single shot, but take good aim; nor touch a trigger, till you can see the whites of their eyes."

"Powder was scarce and must not be wasted. They should not fire at the enemy till they saw the white of their eyes, and then fire low, take aim at their waistbands. They were all marksmen, and could kill a squirrel at a hundred yards; reserve their fire, and the enemy were all destroyed. Aim at the handsome coats, pick off the commanders."

https://www.nps.gov/bost/learn/historyculture/bhm.htm

https://boston1775.blogspot.com/2007/06/who-said-dont-fire-till-you-see-whites.html