To create a deceptive impression or a false front, often by making noises or showing activity where there is none, to mislead an opponent (referring to an ancient military stratagem).
敌军以为我们还有重兵把守，其实那不过是悬羊击鼓，饿马提铃的障眼法
The enemy thought we still had a strong garrison, but in reality, it was just a deceptive trick of hanging sheep to beat drums and hungry horses jingling bells.
Next Idiom