This is a good question that we reveived from a member in our private Facebook group. Feel free to join.
This examiner had this to say.
Generally, the best way to improve your vocabulary is reading. Read a newspaper online for example, and make a note of the vocabulary that appears that you don’t know. Don’t just copy the word but copy the whole phrase.
Why copy the whole phrase?Well, the people that lose Lexical Resource marks are the ones that do one of two things.1. They don’t have the language to be specific enough and so collocation is faulty or possibly spelling too. This is Band 6.0 and below.2. They try to use synonyms that they have learnt from word lists. The problem is that these words are used in specific contexts and cannot be used in the context that the candidate has used them in. This is then considered an error.A lot of the writing I see is generally Band 7.0 level in terms of range. The most common problems I see are spelling, collocation, incorrect context and lack of specificity. It is the errors that usually drop people’s scores.So reading is the key.
If you aren’t sure of what to read, there are some novels here that are suitable for English learners in the Reading fluency – Novels section. We also recommend reading a newspaper. If you don’t read one regularly, read one before your exam so can support your ideas in the writing and speaking exam.
Good luck