Your amaryllis bulb uses the foliage to produce enough food to rebloom next year, so having the leaves last is important. You should get 3-4 leaves that grow out after the bloom is gone. these bulbs do better if you can plant them in the yard as attempting to grow them in the pot is a real challenge. At the end of the season, dig them back up, let them dry for a few days and store them in the coolest location in your home. Sometime after January, you can pot them back up, bring them into a warmer location with lots of light. Your bulb may not bloom again next year since your leaves have been dying off. you can still grow it in your yard as the foliage is quit nice. After a good growing season, blooming will begin again the next year.
Good luck, Richard