Dig a hole 1 foot deep for each lily bulb you are going to plant. Fill it with a mix of soil, compost and peat moss. The peat moss will improve the drainage and the compost and soil will make a rich soil for the bulb to grow in. Space the bulbs 1 to 2 feet apart, depending on the size. The bigger the bulb, the more room they need.
Measure the bulb's diameter using a ruler or tape measure in centimeters. Multiply that number by three and that is how deep you need to bury the bulb. Lily varieties vary greatly so measuring helps determine the needs of your particular species. In general, the bigger the bulb the deeper it will be buried.
Cover the bulbs with soil and water the soil thoroughly to ensure the water reaches the bulbs. Water the bulbs daily until you see shoots, and water as needed after that.
Cut the lilies to ground level after each frost so they will survive the winter and thrive in the spring.
Mulch your lilies every spring with an organic mulch like bark or compost and add a 20-20-20 fertilizer. They do not need more fertilizing than this. Stake the stalks if they look like they can't support the flowers. Most varieties don't need to be staked, but some do.