i was having difficultys too. this is what helped me. make sure that the aptv is not plugged in to the wall, just usb. also, it took forever for my itunes to check my library, and i'd get the error message. season pass was able to make the patched apple tv .ipsw in my finder. soooo.... i just optioned clicked the apple tv in itunes and restored from the patched ipsw from finder. walla!
now that is jailbroken, the tethered boot. make sure its unplugged, plug in usb, wait for it to flash rapid, then plug in power, then hold menu/play for 7 seconds, then plug in the hdmi before it stop flashing.
once you get the hang of it, it's not so bad.