I passed it last summer... JUST
67/100
*beers for all!!!*
so that was the 2004 B I think.
What you have to do is get about 3-4 past papers and practise them. Best to buy the paper and photocopy it so you don't waste it if you mess it up.
Once you've completed it, let your tutor go through it with you if possible. And move onto the next specimen. Just keep doing these papers on a weekly basis (or however often).
The key is to get "used" to the theory exam layout. Splitting the 3 hours over the 5 questions, evenly, depending on difficulty and your abilities.
The first 3 are generally half hour questions, though the sooner you do them, the more time you have for the 4th and 5th.
Q1+2 has been done to death... just watch out for patterns to repeat and double check to make sure you haven't written parallels into the music.
Q3 is fairly open - I recommend string instruments, due to their range and their many articulations and decorative "bits" you can give.
45 minutes for Q4 and Q5.
Those involve reading scores and finding chords, background knowledge of composers, history, etc etc.
keep the ball rolling. so you don't have to rush the last moments.
and read up on the vocab at the back of the AB guides... both of them.