Note: sorry, I meant 116/120!
I did not prepare at all for this test. I was quite tired as it was during my end-of-semester rush (exams, papers to hand in, etc). I had studied for my Ancient Greek exam during 5 hours that day... So, I arrived to the test centre exhausted and unprepared. There were numerous problems at the centre (they would not accept my ID cards, since they did not figure on their "acceptable american ID card" list. I'm in Canada, we do not have State ID nor national ID here, I do not drive, so I do not own a driving license, I have never needed yet to have a passport made, so I do not own one, but my medicare card is a perfectly valid ID card, and the closest thing we Canadian have to a national ID card!). When I was finaly let in, I was almost crying.
Still, I've gotten 116 out of 120. I received a perfect score in every section beside speaking.
What baffles me is that, whilst I think my English is good, it is still far from perfect. I cannot compose in English as easily as in French and I feel that my knowledge of the English grammar leaves a lot to be desired. Surprisingly, I even scored higher than my boyfriend, who has been studying philosophy in English universities for 5 years or so (this angers him quite a lot!). He was not as tired nor as nervous as I was and his English is definitely better than mine. There's not way to tell it's not his mother tongue.
So, this test is not very hard if you read a lot, have taken some classes in English and practice every so often. I do not think that there is much to do to prepare. One simply need to be good all over. Beside, the test is made so you do not have time to prepare yourself: you must answer fast and well. This is especially true of the speaking section.