Related Rule
Israel
Practice Relating to Rule 57. Ruses of War
Israel’s Manual on the Laws of War (1998) states:
Surprise, stratagem, artifice are some of the most fundamental principles of war, giving the army a tactical advantage, and sometimes even a strategic one. The prohibition in the chapter on methods of warfare does not come to deny the armies the use of the element of surprise or to demand that each side be “transparent” to its enemy.
There is no prohibition on the use of camouflage, stratagems, ambushes and deceptions that are not perfidious means, i.e. where there is no situation of trust between the parties by virtue of the law of war, which is violated by one of the parties. Thus, for example, camouflaging a combatant to appear like objects in the natural surroundings (as opposed to the human surroundings) is permitted (such as painting the face black, adding leaves to helmet, and so forth). Interfering with the enemy’s communication network and conducting psychological warfare are permissible …
One may deceive the enemy with regard to the size of one’s force or its intentions, as was done in the Yom Kippur War by the “Zvika Force”. It is also allowed to conduct maneuvers of deception, flanking, dummy units and weapons, and the like. The law of war does not come to bar any party from exploiting tactical or strategic advantages or the enemy’s naivete. 
Israel, Laws of War in the Battlefield, Manual, Military Advocate General Headquarters, Military School, 1998, pp. 56 and 58.
Israel’s Manual on the Rules of Warfare (2006) states:
Combatants must wear a permanent sign of recognition which can be recognised from afar … Naturally, this does not mean wearing identification that is likely to endanger the wearer (such as a hat that is luminous in the dark) nor does it prevent the use of camouflage that makes use of the conditions in the field (hiding among trees and bushes). 
Israel, Rules of Warfare on the Battlefield, Military Advocate-General’s Corps Command, IDF School of Military Law, Second Edition, 2006, p. 31.
The manual further states:
Surprise, deception and dishonesty are among the most basic principles of war, gaining a tactical and even a strategic advantage for the army. The ban in the annals of the rules of engagement is not designed to prevent armies from using surprise tactics and does not require each side to be “transparent” in the face of its enemy. The distinction between trickery (which is permitted) and betrayals of trust or treachery is that the latter are defined as acts designed to cause the enemy to think that it is entitled to the protection of the rules of war or to create a situation in which it is obliged to put its trust in the opposing side through the intention to betray such trust. 
Israel, Rules of Warfare on the Battlefield, Military Advocate-General’s Corps Command, IDF School of Military Law, Second Edition, 2006, p. 35.
In addition, the manual states:
There is no ban on using deception, trickery, ambushes and misleading tactics that are not treachery. Take, for example, a fighter concealing himself in features of the natural (as opposed to the human) surroundings (It is permitted to blacken the face, add leaves to the helmet, etc.). It is permitted to disrupt the enemy’s network of communications and psychological warfare is also permitted. During the Gulf War, the Coalition planes dropped “safe conduct passes” over the Iraqi army soldiers, promising immunity to any soldier showing the slip of paper and laying down his arms. It is permitted to mislead the enemy with respect to the size of your force or its intentions as was done during the Yom Kippur War by the “Zvika Force” and it is also possible to use false manoeuvres, outflanking movements and decoys. The rules of war are not designed to prevent the use of tactical or strategic advantages or the naivety of the enemy, but to lay down basic rules of the game so that anyone who is entitled to be protected is not frightened to lay down their weapons. 
Israel, Rules of Warfare on the Battlefield, Military Advocate-General’s Corps Command, IDF School of Military Law, Second Edition, 2006, p. 36.
The Manual on the Rules of Warfare (2006) is a second edition of the Manual on the Laws of War (1998).