Writing a novel fast requires focus and discipline. Eliminate distractions, write in blocks of time, and don't get bogged down in perfecting every sentence in the first draft. Just get the story down.
Another fast way is to set a daily or weekly word count goal and stick to it religiously. Don't worry too much about perfection in the first draft. Just get the words down. You can always go back and edit later. For instance, aiming for 500 words a day might seem small, but over a month it can add up to a significant amount of your novel.
There are indeed books on this. 'The First 5 Pages: A Writer's Guide to Staying Out of the Rejection Pile' is relevant too. Although it doesn't solely focus on writing fast, it gives valuable advice on how to start strong, which in turn can make the overall writing process more efficient. If you start well, you're more likely to keep the momentum going and finish your novel faster.
One way to do it is to plan your story thoroughly before you start writing. That way, you know where you're going and can write more smoothly. Also, limit distractions and set a timer to keep yourself focused.
One way to write a good novel fast is to have a clear outline before you start. Know your beginning, middle, and end. That way, you won't waste time deciding what comes next.
First, come up with a strong central character. Then, have a clear beginning, middle, and end in mind. Don't overthink the language; just get your ideas down. Cut out any tangents that don't contribute to the main story.
First, decide on a clear theme. Then, make a quick mental map of the plot. Start writing and keep the flow going. Don't stop to correct mistakes until you're done. That's how you can write a 500-word story fast.