After seeing how easy that can be, I have decided I will continue with staying clean, exercising, drinking tons of water for the next 6 days.
Drinking water is only helpful on the day of the U/A. Drinking "tons of water" in the days before a U/A is of no help. THC is fat soluble, not water soluble. You can't flood your body with water or fluids and clean it out like you would pressure wash your driveway. The rate at which THC metabolites are eliminated in urine is governed by your kidneys' Glomerular Filtration Rate (GFR). Once properly hydrated, you cannot increase the GFR by increasing fluid intake. If you keep drinking and drinking fluids and your body didn't regulate itself, you would die. To control this, your kidneys will pull water from the bloodstream and eliminate it to make up for the excess fluids you are drinking. During this whole process, you will not make your kidneys work better because you are taking in excess fluids and going to the bathroom more often. You did not increase how effective your kidneys are eliminating THC metabolites from the bloodstream. All you did was increase the amount of water in your urine.

When you drink a lot of fluids on the day of the test, this is know as the dilution method. You are not passing the test because you cleaned your body of THC metabolites. What you have done is you have decreased the concentration of THC metabolites in the urine by increasing water. Just like adding paint thinner to paint - the concentration is reduced but paint is still there. As Ive previously pointed out, the dilution phenomena is only temporary. Once youve urinated out the water that have been consumed, the bladder is replenished with fresh THCA-laden urine by the kidneys - back to square one.

Exercising can be detrimental if a person has 3 days or less before the scheduled U/A. Exercise burns fat cells. When a fat cell burns, the stored THC metabolites are released back into the bloodstream, filtered by the kidneys, and deposited into the bladder for the eventual exit. Therefore, if a person is failing home tests (with the first urination of the day) and the scheduled U/A is 3 days away, then all exercise should be curtailed and the donor be as dormant as possible until after the U/A. That way the donor wont be releasing a bunch of THCA back into the bloodstream, which will end up in the urine to be detected.