Caring for the amaryllis after it blooms requires you to cut the bloom off the plant and move it inside to a less-stressful environment. You can move the plant outside after winter has passed to restart the growth cycle.
When you cut the flower off, use shears and cut just a few inches above the bulb. Take care to not harm the leaves. Moving the plant to an indoor yet sunny location allows the plant to manufacture food for itself with the power of sunlight, yet stay strong because it is not outside in the middle of harsh winter weather. Water the plant if the soil gets dry.
The plant should be moved outside in the beginning of summer, around the end of May or the beginning of June. However, the plant should be acclimated before it is fully moved outside. Leave the plant outside in a safe, not-too-sunny area for a few days, and then move it back inside for a greater amount of time. Alternate leaving the plant outside and leaving it inside, letting the plant stay out for an increasing amount of time, until you effectively wean it off the indoor climate. Once the plant flowers again, repeat the process for the next year.