The Writing aspect of certification exams tends to be the most difficult of the four. Students scores are 10-15% lower than in the other aspects. To avoid making typical writing mistakes you should know the most obvious ones.
Single-paragraph Essay
A text without proper structure is a text that never gets high score. This text has no clear structure and therefore is both hard and unpleasant to read. Remember that your essay should have at least two body paragraphs, introduction and conclusion. See this essay structure page for more tips.
Copying the Task
Using the same exact phrases from the task isn’t welcomed by examiners. The copied text is not going to be counted towards your total of words. This means that if you use the task words and phrases in your introduction then your essay will basically have no introductory paragraph. This is going to look bad then. Just paraphrase the task, it’s easier than you think!
Draft Essay
Most schools emphasise the importance of writing a draft paper before producing the final work and handing it in. Although this makes perfect sense in the usual studying environment, your writing part of IELTS/CAE/TOEFL is a rare exception. You are guaranteed to have no time to copy your draft to the exam form. And whatever you have written on your draft paper is not going to be scored in any way, even though you are asked to hand that in too.
If you are worried about corrections in your exam paper — don’t be. Corrections are not punished at all as long as the corrected phrase is written legibly (i.e. it is easy to understand).
No Planning
This writing mistake is related to the previous one. While making a full draft paper isn’t advised, planning your structure beforehand is still encouraged. Take a few minutes to decide how many paragraphs you will have and what they will be about. Such brief outline will ensure smoother transitions between ideas and overall better cohesion.
Easy Goes First
It is tempting to go for the shorter and easier writing task first (Like Task 1 in IELTS which is 150 words as opposed to 250 word Task 2). This approach is not sound because the bigger and more challenging task brings your more points. If you find yourself running out of time then it is better to have finished your second task.