“23. The Book of Army Management says: On the field of battle, the spoken word does not carry far enough: hence the institution of gongs and drums. Nor can ordinary objects be seen clearly enough: hence the institution of banners and flags.
24. Gongs and drums, banners and flags, are means whereby the ears and eyes of the host may be focused on one particular point.
25. The host thus forming a single united body, is it impossible either for the brave to advance alone, or for the cowardly to retreat alone. This is the art of handling large masses of men.
26. In night-fighting, then, make much use of signal-fires and drums, and in fighting by day, of flags and banners, as a means of influencing the ears and eyes of your army.
27. A whole army may be robbed of its spirit; a commander-in-chief may be robbed of his presence of mind.
28. Now a soldier’s spirit is keenest in the morning; by noonday it has begun to flag; and in the evening, his mind is bent only on returning to camp.
29. A clever general, therefore, avoids an army when its spirit is keen, but attacks it when it is sluggish and inclined to return. This is the art of studying moods.
30. Disciplined and calm, to await the appearance of disorder and hubbub amongst the enemy:–this is the art of retaining self-possession.”
Sun Tzu, Master Sun
Art of War
Quoted in The Art of War, Translated by Lionel Giles, Offered by The Project Gutenberg eBook

Unify through commands
Lead through vision
Forming a single band
Mastering precision

Unify and Lead respectively
Rob the enemy’s spirit to lower productivity

Avoid when the enemy is at its keenest
Attack when they are at its weakest

Use the art of psychology
Disorder and confusion will be their enemy