The easiest way for me to get the "required" amount of water is to keep a 1 liter (~1 quart) bottle with me at the office, and sip on it all day. I normally fill it twice at the office; once in the morning and once in the afternoon. I'll normally drink 1.5 to 2 bottles while at the office. During the course of the full day, I'm drinking 2.5 to 3 liters (about 2.5 to 3 quarts) of water per day. Once I figured out that 8 cups is about 2 quarts I decided to stop counting cups and use larger units so I don't have to keep track as much. It's much easier for me to remember I had 2 bottles than it is for me to try and remember how many cups I've had throughout the day.
At the end of the day, I'll top the bottle off and take it with me to the gym. I get my cardio in and then sip on the water while I strength train.
I do it to stay hydrated, and gauge my current levels of hydration on the color of my urine. The darker it is the lower my hydration level. The lighter the color the better my hydration. I neglected to maintain proper hydration during a field operation while I was a Marine once, and don't care to have a repeat.
Sipping on the water throughout the day gives the water time to be absorbed by my body. So, I'm not running to the bathroom every 5 minutes.
I'm also another morning coffee drinker, and the extra water helps.