A timing light, some chalk or a silver sharpie marker (my personal choice) and either a dizzy hold down wrench or a means of loosening the dizzy hold down (I use a 1/4" drive wrench, extension and socket with a swivel).
I guess it depends on whats wrong with the timing. Are you just trying to set the timing? If so, you will need what Hissin50 wrote above. Just remember that you will need to disconnect the spout when setting the timing. Stock is 10 degrees BTDC, but alot of people set it at 12 to 16 degrees for a little better performance, just depends if you experience knock or not.