My advice is to go over several of the guides (like Titanium Bits), solve all GRE practice booklets and past exams in existence - you should have no problem finding them (I would put my archive, but this forum seems pretty tight on copyright issues, which I could care less about, but since I'm a guest here... but I digress.)
Anyway, when you solve the practice booklets and the past exams, refresh your memory on everything you don't understand or remember. If you had good education, this should be enough. E.g., I completed the B.Sc. in 2000, so your 2004 is pretty fresh. :)