You have 3 main steps.
- Offer them materialistic things upfront so even the most skeptic person sees the value of following your rules, even without believing.
- Engage in long term brainwashing and social engineering complete with spying and elevating those who obey you
- Go for the second generation of the original patch and control their culture. Those 2nd gen kids would be your absolute most fervent followers because basically you had them from birth.
The first thing is obvious. History is full of city or country or group A that joins religion X just for the cool stuff they give out and overtime they are converted. Yes violently forcing people to follow you exists. But you don't have to and honestly with a PA setting you really need just about all humans you can.
So. Focus first on helping people. Be kind and gentle. Provide all the helpful things people need while ever so gently nudging them to follow you.
People feel gratitude towards those who help them and many confuse material power for being right.
The next thing is what I think is missing from answers so I will try to cover it but also not drown you in details.
Machiavelli was clear that you need the power of the state to keep people following your ideas. He gave examples and I agree. The USSR would not have lasted even a decade without a lot of the practices, good or bad, of Stalin and overall dictatorship.
So. History is your friend here. First reward those who obey you. Then reward those who inform on people that have impure thoughts of doubt it. I read that in the USSR 1/3 was an informant. Now be careful and filter the info from people who want to exploit the system. So. If someone comes with information that another person is doubting your ideas double check it first. And if the informant lies then you know what to do.
Speaking of that prison, hard labor, torture...etc all work as strong deterrent.
People are less likely to practice their freedom of speech if they know that your own Lubyanka is up and running and welcomes all.
Here you also constantly indoctrinate people with stuff like: mandatory weekly meetings, controlling the entertainment, testing people in your dogma...etc
Basically you are looking to not only introduce people you your ideas but keep them practicing it and at least knowing about it for survival.
Now people are very different and I know for a fact that many would resist.
But let me ask you this: How many people you know will continually reject a dogma after 20 years of continues practice?
This is I think the most critical step. Keep the people doing it long enough and they just forget or don't care. Your mind is only concerned with survival and as that dogma is the only way for survival it would probably push all others.
The real children of Radiance
Even with all that the first generation is not pure. The second one is the purest. Those whom you shaped from birth. You controlled their entertainment, their daily practices, their education, their entire life...etc.
The most fanatical of the bunch are those. In fact from what I know about the human mind those after a certain age are difficult to brainwash. But if you get kids young enough it's free real state.
Obviously you can control the first gen, examples are plenty, but the total control and indoctrination is the 2nd gen.
They would be loyal to your ideas or your own self beyond even that of their own families. Again drawing from the USSR family members informed on each other.
And here is a little interesting anecdote. This is from memory so bear with me:
Basically a devout party member imprisoned. She was totally pure but as the men came to take her she was not interested in saying goodbye to her children and kept defending the party and ideals. They even told her that just say goodbye to your children instead of this rubbish. Anyway in prison her own children were shocked and basically were accusing her of being impure and all that rubbish, but also wondering how can she do that so that to them because with a political prisoner mom they had no life in the system and were denied many things.
Again sorry for butchering the story but the moral is this: She did not doubt for a second that they system could be corrupt or even wrong, she blamed herself. Her children blamed her and had no petty for her. That is next level social control right there.
Solzhenitsyn says in his The Gulag Archipelago that the worst type of prisoners and those who suffered the most were not the political ones but those pure communism believers. Yep. You read that right. Many kept denying that the system was flawed even if they were in the f**king Gulag and wrongfully imprisoned.
I mean if I tried to write that in a story people will call me crazy.
Yes. It's easy for you and me to look back at those things and judge, but life is not really that easy.
And for extra points in controlling the people just read on China, RIGHT NOW!
I don't mean to make it political or anything like that. Just drawing inspiration from history and what is done.