One very good example of propaganda comes after Snowball's expulsion from the farm, and after Napoleon has declared himself de facto leader. To convince the animals that this leadership is necessary, Squealer uses the following argument:
"I trust that every animal here appreciates the sacrifice that Comrade Napoleon has made in taking this extra labour upon himself. Do not imagine, comrades, that leadership is a pleasure! On the contrary, it is a deep and heavy responsibility."
(Orwell, Animal Farm, msxnet.org)
By declaring that Napoleon's actions are to benefit the entire farm, instead of just himself, Squealer convinces the animals that leadership is not actually rulership, but just another form of equal labor. Since someone has to make the hard decisions, it is noble and selfless of Napoleon to take that burden off the other animals, leaving them to work in the assurance that they are being properly represented. Of course, this is all a lie calculated to help Napoleon gain even more power, but it is delivered with conviction and with the implicit fear of Napoleon's trained dogs.