New Model Radical

People talk to themselves; they send themselves messages on all sorts of topics. Notably, if you want to get a message across, you must consider...

• The source. If you'd like to give your message extra weight, you want to either possess, or seem to possess, practical skill or expertise, general virtue, and a deep love of your audience.
• The reasoning. A strong argument is, or at least seems, rational. A sale, with lowered prices, is a rational-appeal argument to buy now instead of later. But if you push a sale at people who would not have bought later (or at all), it merely appears rational; the real rationality departs for both buyer and seller.
  
• The emotion. Specifically, the emotional appeal attached to the message. Heavy emotional appeal can carry a no-source, no-reasoning message easily. Novel messages have emotional appeal even when they're not loaded. Even the use of loaded words (for example - new, quick, easy, improved, now, suddenly, introducing, and amazing).
• The circumstances. Messages are not passed on in a vacuum. A personal testimony from a friend over coffee is much more potent than the same testimony from a stranger interrupting your morning over the phone. The intensity of the message, and the likelihood of repetition, are contextual.

Some of that might not be stated all that well, but this is a pretty ancient hat - in greek rhetoric, the first three elements there are called Ethos, Logos, and Pathos. So, not really news. The news is that this same set of components can be used to convince yourself of things.

Extreme political views, deep subcultures, and many other kinds of ideation were once fairly rare to actually run into. But now, with widepread instant media for all niches, it's far easier to find and sample a palette of extreme viewpoints, to the point where they seem usual. It's easier to make yourself into a radical. That's not necessarily a bad thing in every instance; radical feminism certainly needed to exist (it might well still need to exist). But it's also safe to say that it's easier than ever to convince yourself of something that is simply batshit crazy.

Consider...

• Sources. You'll need to find sources that you can paint as having practical skill or expertise, general virtue, or a deep love of you. Defend these viciously and unthinkingly; the act of defending them will help you convince yourself of their perfection.
  
• Reasoning. Find a shopping list of arguments that support your desired view. They don't need to make great sense, but they do need to make enough sense that you can skate through them without too much cognitive dissonance. If there's a solid premise, buy that first and use it often; it makes swallowing otherwise ridiculous arguments in the same vein much easier.
  
• Emotion. You should be able to find arguments that provoke fear in you where they are intended to, inspire you where they should, and get the blood racing in all the right ways. Hang on to them. Circumstances, however, are key here...
  
• The circumstances. Try to surround yourself with others (virtually or actually) that idolise the same sources and vilify the same critics. Together, practice your accepted arguments as pat responses, and shop for things that can make you angry or related as a whole group - you'll want to rage together and celebrate together to enforce your radicalisation. If you can't get a group together, isolate yourself, think hard and long about how misunderstood you are, and surround yourself with agreeable authors.
  

Now, individual bits of the above are normal human behaviour. You can even have a watered-down version of the whole package, and have it be no more that a strong bias. You're going to need to push hard here, but the tools are right in front of you.