Drinking a ton of water does not work anymore. They now test the specific gravity of your urine, so if you dilute it by drinking a bunch of water you will not pass.
The only real way to pass these days is by substitution. However, you would have to know whether or not they observe it coming out of your penis. You get some clean urine from someone, find a small flattish container, heat up the piss for about 10 or 15 seconds in the microwave, then strap one of those hand warmers to it and keep it in your crotch. It'll stay the right temperature indefinitely like that. If you go to the head shop and buy one of those synthetic urine kits, they will have the bottle you need with the temperature gauge on it. However, it's much better to use someone else's clean urine rather than that synthetic urine because the drug testing people are really up on that and unless the synthetic urine company is constantly making the right changes, you could very well fail with that stuff.