I am assuming that you mean Spathiphyllum or the Peace lily plant? If so, I do follow these steps to get my Peace lily to bloom every summer.

1. These plants require a good balance between light, temperature and humidity in order to bloom.
2. They won't bloom unless the temperatures reach a good toasty value of at least 75° F.
3. I take good care of my plant even when it is not in bloom. That way, I can ensure that the plant is in good health to bloom when time comes and also, I get to enjoy the lush green foliage (variegated in case of my plant!).
4. I water as and when the leaves begin to droop. I never overwater. Peace lilies are very good at telling us when they are thirsty by drooping their beautiful leaves. Once they start to droop, water them at once and they will recover. If you let the leaves droop too much, they won't recover.
5. Even though the peace lily is termed as a “low light plant”, it requires a good amount of bright but indirect light in order to bloom. Please note that they don't like hot direct sun. I have my plant near a shaded West facing window where it gets dappled sunlight through the blinds for a few hours in the afternoon. The blinds help reduce the intensity of sunlight and also emulates the forest floor environment!
6. Every spring, I divide the plant, repot it into new soil and cut off some of the outer old leaves. This paves way for new growth and if you notice closely, the blooms usually emerge from the new growth!
7. I am not very consistent with fertilizing. In my opinion, too much fertilization tends to burn the roots and does more harm than good. I do fertilize the plant with a diluted solution of indoor plant food sometime during spring and summer. My peace lily likes it!