I received a little evergreen tree as a present and I'm killing it! A woman at the local flower shop told me to let it sit in water for a couple of hours and now I believe I've over watered it. Is there any hope to save it? I'm not very good with any type of plants, so any advice would be greatly appreciated.

Thanks,
Nicole

Plants should not be allowed to sit in water which can cause rot rot, the soil should have excellent drainage and any excess water spilled out of saucer right afterwords.
You say it's an evergreen tree? Maybe a Norfolk Island Pine? Let the soil dry out a couple inches or so from the top before watering it again.You want semi moist soil, not dried out and not soggy wet.
Give it bright indirect light and protect it against direct hot sun in the summer months. Try to provide a cool room vs a warmer one which can dry out the branches and needles. Keep it away from direct heat sources. Don't feed in winter.