What is the best way to become a novelist?

Just write heaps of novels and submit as many as you can! Most likely you won't get published on your first try, and if that's all you're trying for, then you should forget it. But just keep writing. And write things you would read. Perfect it - edit, read, reread, check grammar, sentences, everything - and then submit it. And then hope for the best. You can't just learn to be a writer. You can learn to construct stories, etc., but you can't learn to write, if that makes sense.