Cleaning a fake Christmas tree is a bit different than cleaning a real one, but it can still be done fairly easily. First, you'll want to gently remove any ornaments or decorations from the tree and place them aside. Next, using a soft brush or a vacuum with a soft attachment, gently brush or vacuum the branches and trunk of the tree. Be sure to go over the entire tree thoroughly, including the underside of the branches, to remove any dust or debris. Finally, wipe down the tree with a damp cloth to remove any remaining dirt or grime.