Light
Like most plants, Peace Lilies prefer bright, indirect light, but will adjust and even thrive in lower lighting conditions. You will often see Peace Lilies in offices or hallways because they do so well in low light. Even overhead fluorescent lighting can provide adequate light.
Keep your plant away from direct light. Peace Lilies are shade-loving plants and will get sunburned if exposed to direct light even indoors. However, keeping them near a window (within 3 feet) will help them flower consistently all year.
Water
Peace Lilies prefer a deep watering once they dry out. Allow the top third of the soil to dry out before watering. The best thing about Peace Lilies is they will show you when they start to get thirsty. The leaves will start to sag as it dries out, and actually droop dramatically when it is time to water. This is a great indicator, however, this does stress the plant out so watering before your plant droops is best.
Fertilizer
Use an organic house plant fertilizer once a month during the Spring and Summer to give it a boost. Hold off on fertilizing during the Fall and Winter. Peace Lilies are a bit sensitive to chemicals, so using an organic fertilizer is best.