Hi Ruby,
First, cut off the
flower stalk at the base and discard it. Presumably, your bulb has produced a few leaves or will soon.
Gently put your rooted bulb into a pot just a bit wider than the bulb and use a soilless, peat-based potting mix to fill in around the roots. About half of the bulb should be ABOVE the potting mix.
Place your Amaryllis bulb in your sunniest window. Water as soon as the top inch of potting mix feels dry. Fertilize monthly at half strength.
When temps are above 55 degrees, you an move your Amaryllis outside into a shaded spot, if you like.
In the fall, stop watering and move the
plant to a cool, dim, dry location. Allow the leaves to die back as the
plant goes dormant for about 8 weeks. After that, you can resume watering it and you shoud get a new round of
flowers for the holiday season.
I have written an article on holiday
plant (Amaryllis, Poinsettia, Holiday cacti) care that I will email to anyone who sends a request to me at wcreed@HorticulturalHelp.com