Margaret and Gale - I don't know when the best time is for you to divide for your zone 6, but as far as dividing ...
I use a garden fork (like a pitch fork) to lift the daylilies out of the ground. A garden fork prevents a lot of cut off root damage that a shovel would probably cause. I just push the garden fork in about 6-8 inches out from the base of the plant circling the plant and lifting. Eventually, you'll have loosened the roots enough to lift the plant out of the ground. Then I, personally, gently use my hands to separate the fans, but some times you really have to tug to pull them apart. Other folks I know just cut through the clump with a shovel. I hate wasting (damaging) fans, so that is why I use my hands to pull them apart. I have also heard of using TWO garden forks back-to-back to separate them.
Char wrote an article about dividing them:
http://garden.org/ideas/view/C...
Her photos are excellent and the article should be very helpful to both of you!
