Take regular breaks after 30 minutes of rapid reading get up and move away from the book for 5 minutes. One of the things that slows us down is that we've been at it too long without a break.
Also one novel... for pleasure reading, well if you want to get better at it and faster at it tackle more novels. Beware that pleasure reading sucks us in to slower reading and that's fine if we seek that however we tend to get the reading done in the time we have available best if we know we only have a certain period of time to finish so another way to push your reading and not get stuck on every word is set a stopping time and stoping point.
Alex