One of the most important is the use of outside events in the way that will compel the citizens (held in ignorance of the truth) to do what those in power want them to do. If you are the Soviet Leaders you can teach your people that the people of the United States (or any capitalist country) are miserable slaves to the wealthy elite and that they are simply waiting to be freed from those shackles to rise up against those oppressors.
This is in many ways mimicked by the way the pigs use different events and manipulate the truth so that they can get the desired effect from the actual event. Boxer is sold to the knackers but supposedly went to the hospital and got the best care possible. This helps the populace to retain their dream and idealized view of the leaders. There are myriad examples in the story.