An amaryllis prefers a very bright, warm location. Try to avoid full sunlight but, keep it in a sunny window.
When the bulb is not in bloom let the soil almost completely dry out. When the growth begins to sprout gradually increase the water to keep it uniformly moist. After the blooming has finished, cut off the stalk and fertilize weekly until August. Then, start to decrease the water amount and allow foliage to die. Continue the process.
Key tip for success: When planted, half the bulb must show above the soil.