I'm not familiar with that method precisely, but skimming it, it doesn't sound too different from my own method.
Starting with core ideas is obviously essential. Start trying to figure out the directions that you want the plot to take and the biggest story beats, then start mapping it out into a coherent story. You don't need to spontaneously know the whole novel in one sitting. I typically go from like a key plot concept to general plot points and then organize them and refine them over time.
The biggest thing that helps me, though, is to get a physical notebook to jot ideas down on. Having my ideas on paper helps so much, and in particular, I make pages for each character to help write out traits or quirks or just smaller details as I develop them. Even if they aren't all important and are just mentioned in passing (or maybe not at all), developing your characters like that really helps.
When you get to actually writing it, pacing is really important. I tried to just attack it on my first time writing a novel, and I burnt out pretty hard and didn't feel up to writing for quite a while after that. Even "a chapter a day" isn't always realistic when it comes to longer chapters. My biggest advice there is to just try to write something every day. Even if it's just a few sentences, keep making progress without pushing yourself too hard.