Answer: Hey, isn't this gardening fun? Especially bulbs!
Don't do anything with them. Leave them in the ground and allow the foliage to die back naturally. Don't cut the foliage off. If you're feeling ambitious you could fertilize them a bit now because as the leaves die back, they're feeding those bulbs and getting them ready for next years bloom. There are fertilizers made especially for bulbs. They should be available at your local garden center. With just that little bit of help they'll come back again and again each spring! Wasn't that easy? [If you ever plant tender bulbs like gladiolus, you need to dig those up and store them because they can't withstand the cold. But tulips, daffodils, and crocus can all take the cold just fine!]
By the way, you don't need to "trick" your bulbs into dormancy. You have WINTER which does it for you! That's only necessary for people living in regions where they don't have cold winters.
By the way, there's a neat web site provided by the Netherlands Flower Bulb Information Center. They have all kinds of tips. The address is: http://www.bulb.com
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