Today, the new varieties of poinsettias, like the one you are holding here have been bred to retain their flowers long after the holiday season has past. Just keep the plant on the dry side, avoiding over-watering. Remove any yellowing leaves. When the flowers have faded, remove them. Soon you will see new leaves sprouting. Grow on and enjoy as a foliage houseplant.
Tip - When selecting a poinsettia, consider whites, creams, pinks and marbles for a less traditional color that will continue to look good long after the holiday season.