You need either a H-alpha solar filter, a Glass Solar Filter or Baader Solar film. I doubt that you'll be able to find any in time, around here they are all sold out.
There a no special settings that work, so much depends on the atmospheric conditions, camera, optics, filters, focal length, f-ratio, etc.
http://www.bautforum.com/showthread.php/134095-I-want-to-photograph-the-transit-of-Venus-and-need-some-help
