What to do with daffodil plant after flowers die off?

Here you go!

http://homeguides.sfgate.com/daffodil-care-done-blooming-30285.html

As soon as you ground is workable ,dig the whole twice the size of the pot and plant everything

No, don’t let it dry out, plant it in the ground and water it as you would any other outdoor plants. It will bloom as usual in the spring.

Yes, you might want to water it as the leaves help build the bulbs up for next years blooms.

I would water it & plant as soon as the ground is soft enough. Don’t cut off the leaves. As they die, they feed the he bulbs.

Plant it outside, along with tulips, poinsettia, and Christmas cactus. Make sure the plants get water, drainage, and sunlight. Dig them up at the end of warm weather and keep them in pots in the cool or cold and dark at least a month. Bring the pots to warm temps in your house and you just might have new flowers next spring. Best wishes ☺️