When the blooms drop off, you have a bud left. Do these rebloom and will they come back next year?
Certified GKH Gardening Expert
When all the flowers have faded, you can dead head the lily stem.
Leave the green stem to die down naturally, since this helps feed the bulb for next years flowers.
Your bulbs bloom one time each season.
Here are some links to refresh you on the care requirements.