1. memorise all the idioms, compositions and sentence structures.
When you don't have much time, my best advice is for you to memorise as many words as you can from your textbook and learn how to use them. It's better to know them than to try to guess it during the exams. If you are able to learn some good phrases for the composition, do it by all means. You can scorn at this method, but it does deliver results.
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4. Comprehension: (I will use Rosyth School's 2011 paper as examples in this segment)
a. Read the passage carefully. If you don't understand what it's saying, look for the common words in the text and question.
For instance:
Q:什么原因造成国王的朋友不喜欢接近他?
In the first paragraph of the passage, you see 朋友mentioned.
"。。。但脾气很暴躁, 要到不如意的事,他就不能克制自己,开始乱骂人。他身边的朋友也开始疏远他."
Let's say you don't understand the meaning of 疏远 or 暴躁. But you understand the words 朋友 and 骂人. You would be able to guess that the answer should be in this paragraph.
b. In comprehensions, they will give you a description and ask you to spot the word that matches it. If you don't know which word is the correct word, read the broader story to get the context.
For instance:
The paper required students to look for the phrase that mean: 做事小心、周到;细心注意。
Let's say we can't find the word. And we read this sentence.
"两年的时间过去了,国王谨慎地除下面具"
Imagine: you had to put on a mask for two years. Taking the mask off would be a great deal and you will do it carefully, right?
So we can assume 谨慎 would mean 做事小心、周到;细心注意.
c. Sentence construction- In comprehension, they may require you to use a word from the passage to construct a sentence. This was in the Rosayth Sch's Higher Chinese paper in 2011.
For instance:
Question: Construct a sentence using 麻烦.
It's really tough if you don't understand the word. You could try to guess it using the context from the article as previously mentioned.
If you understand the word, but don't know how to use the word/phrase, you could try to mirror the way the passage used it.
Always remember, in sentence construction, your example must illustrate the meaning of the word.
This is from the passage: 这段日子麻烦你了。
I could follow the same sentence structure:
我一直住在你的家, 真的麻烦你了。
(The sentence structure is similar and I explained why I troubled you.)