That whole eight-pints-a-day thing is a bit of a misnomer. Someone on TV said once that a healthy person consumes about this much on a daily basis. That includes the water/fluid you ingest as part of what you eat. However, some people took it to mean that that's what you should consume - eight pints of water.
So if you're healthy and are at a respectable weight for your height, just take the fluids you feel you need, although of course, you should watch your intake of caffeine and alcohol and keep it a sensible level.