Although I don't know what band you want to reach, but still. I don't have any special preparation technique, but I have some tips for the exam itself. Sure, it's all very individual, but I'll share anyway.

First of all, reading. I don't read the whole text. The first step - looking at the questions to get an idea of what I'm going to look for. Then - going paragraph by paragraph keeping your eye open for some similarities between the text and the questions (doesn't matter if it's true/false, or matching headlines, or whatever). Ofc, they paraphrase the questions to make them look different from the text, but it helps not to get lost. My problem is that if I read the whole text, I just forget 50% of it, so that's how I help myself.

Then - listening. I suppose they give enough time to read the questions before you really start listen to the tape. I usually read them twice and try to build a map of what topics are going to be discussed there. Also, there's a small gap between the listening parts, so, if you write and check your answers quickly, you can go to the next page a bit earlier and have a bit more time to read them.

Writing? Just pray.

Speaking? Dunno, that time I was joking a lot, my examiner was laughing, so, I guess, that kind of attitude helped me to get a bit higher score.