I don't measure, but I am pretty sure it's more than the average person.
I drink a cup first thing after I get up in the morning.
I bring a big jug to the gym and take a sip at every set.
I have one or 2 refillable bottles by my desk.
I don't go to bed dehydrated. The downside is I have to p once or twice a night.
I know I drink enough by observing my urine color, I like it clear, or clear yellowish.
I don't flavor it. I don't drink soda, once in a while I will have a coke. I do drink coffee in the morning, and fruit juices sometimes.
Edit: Now here's a funny thing. You might wanna ask, how do I know I drink more than the average person?
First, I observe people at the gym, some don't even drink water. And I have probably one of the biggest jugs in there (other than those with the milk gallon jugs).
Second, if you use a public bathroom, such as at a workplace, you can hear and know how many seconds each person takes for their water to drop
If yours take more more time, and you often use the bathroom, then you are probably doing alright.