i limit fluids the day before and i shit all my shit out hahaha thats usually enough for what i need to weigh... i have to be 159 friday and right now i walk around at 163-164.
I usually drink 2 gallons the fifth, fourth and third day before the weigh ins, 2 days before I only drink one gallon and then I cut out all fluids till the weigh in. I hate having to go to the bathroom constantly.
make it part of your meal plan... don't just count on cutting water... 2 or 3 months out from your comp get a Dexa Scan so when your dropping weight you know if it's fat or muscle.
Weight cutting is a science but it varies per person some people respond better than others. 2-6 pounds isnt much of a cutt so the water cut is ok. I save the last 3-5lbs of water for the day of weigh ins.