I would say, for a beginner, I have to go with Capsulecorp on this one. I love the idea of felt, and I've worked with it before, but a good base of sewing knowledge will then help them develop the skills to work in felt. The type of hat that involves sewing puts it in good set of basic geometric shapes and measurements rather than the more touchy feely but just as serious science of felting and getting that just right especially the first time around.
McCalls, Simplicity, Butterick any halloween costume pattern producing company has atleast one (or should have) good basic witchy hat pattern. These would also include the instructions on how to put it together so that you could further develop your witchi-hatti-ness if you please.
The above pattern includes a witch hat