Actually, for the water consumption, start about 2 days prior. Drink more than you normally do. This is because the body gets used to a certain amount of water intake. It starts to, after awhile, run the body as optimally as it can on what it's used to having. This being said, when you dump a bunch of extra water into your system, the body usually ends up not using it, and you end up just urinating it out, and gain little benefit from the extra intake. 2 days should give your body enough time to "learn" to retain and use the extra water for the day of the ride.