Do you know when it was cut? If it was cut recently (in the last few days) you won't need to make a fresh cut on the stump. If you don't know when it was cut down, make a fresh cut on the stump, taking off a couple inches.
Our trees can take anywhere from a half gallon to a full gallon of water a day...so it needs to be watered daily.
Don't put it up near a constant heat source (heating vent, etc).
I've only ever had fresh trees and that is all I'll ever have.