I used the Kings Course. It was pretty cheesy and had that 1987 VHS feel to it, but, I passed written, oral, and practical on my first try. Things that worked for me:
*diligently did the Kings course
*took all 900 of the Kings questions several times over
*it sounds nuts, but I actually did read, highlight, and bookmark many parts of the FAR / AIM
If I couldn't sleep at night, or had an hour to kill during the day, I would pick up the FAR / AIM and open to page and learn what was on it. Did the same thing with the instrument flying handbook
Like others have said, it is a ton of knowledge and can be very daunting, but if you bight off manageable chunks at a time you should do fine