How do forex traders predict price?

Predicting anything in the forex market is actually impossible. Your best bet will always be to read the price action and act accordingly. Whatever you may read around the internet, no one can predict anything.
Now, how to read & act on price action is the real question. Price action reading means starring at the screen and looking at the price go up and down in certain recognizable patterns. With enough training and knowledge, you'll be able to recognize patterns and trade them with a high probability of success. That's all you can do.
There are great price action strategies out there. The best thing to do is to use the least amount of indicators possible and to really look at the price. Most beginners make the mistake of thinking that they'll find the perfect indicator that will predict exactly what will happen.

The OP of the thread has never made a second post, so I suppose it continues for the sake of others.

My opinion is that predicting refers to fundamental trading and probability refers to technical trading. Since I don't care about fundamentals, I never predict. Since no one knows the outcome of a news report, all you can do is predict, and for me, that is a ridiculous way to trade. It is much simpler to rely on the math and use technical analysis. Is it perfect? No. It is probably though, and that is good enough.