A simple question with a complicated answer. No, you don't cut clematis now - if yours starts flowering around end of June/early July and carries on (should still be in flower now) it's a late one from the viticella group - these should be pruned back to 2 or 3 buds from the ground (usually about 10 inches) by mid-February (not now.) If yours flowers in May, and then again in July/August, these just need a bit of a tidy up after the winter when the growing season begins. Early flowering ones (April/May) don't get pruned either, unless its to restrict size, when that should be carried out immediately flowering is over.

thankyou