1. Introduce oppression as a theoretical idea. Gauge the response.
2. Make oppression optional. Depending on the opposition to the idea (you did remember to gauge the response to the theoretical idea, didn't you?), offer some worthless token that the masses believe has some great value and tell the masses that the oppression is the "tradeoff" needed to obtain the token. Highlight the fact that it is still optional -- if they don't want the token, they don't have to accept the oppression. Some people will buy into it; others won't.
3. Make oppression mandatory for some things. It is essential that you create the appearance that the masses have a choice. Only instead of pointing out that those who do not choose your oppression are missing out on exclusive benefits, paint the opposition as a deluded group of sadists who are "depriving themselves" of "basic rights" to your worthless tokens. This will win you converts, because no one wants to be seen as depriving himself of anything.
4. Make oppression mandatory across the board. If you have followed the above steps, you can now claim that the oppression is the de facto standard that has not only been "accepted" but "endorsed" by the masses. Anyone who questions the oppression can be refuted with this claim, which will strengthen the masses' belief that the oppression is "right" and "good." At this point, you may withdraw the worthless tokens or advance your oppression, because the masses no longer have a choice -- they have already made it and must trust their own judgment.