In general, it is not easy to magnetize a magnet of that size with simple equipment that you can assemble at home, particularly if you want to magnetize it in the thin (1/2 inch) direction. If you have access to a large neodymium magnet, you could try to magnetize the ceramic magnet by contact on appropriate surfaces (the surfaces on which you want to develop poles). If that does not lead to sufficient magnetization for your purposes, there are probably industrial or academic laboratories in your area (with large high-field magnets) that can magnetize your ceramic magnet for you, although the cost of that service might not be much less than the cost of purchasing a new ceramic magnet that has been properly magnetized.