Answers need to be planned, in rough, with a simple list of key factors. This is very useful if you run out of time.
Preferred way to answer questions is through bullet points and explanation. Be careful with "discuss" style questions which will obviously be looking for a more formal answer.
The mark is directly proportional to what is required in the question. So, if the question's worth ten marks and you run out of things to say after three sentences, start panicking.
There is nearly always a question on ergonomics.
Be specific on products, eg. "Dyson DC02 Vacuum Cleaner" not simply "Dyson".
It is not advisable to use examples of products given in the exam paper as examples in other questions. However the same example that you have supplied can be used as an example for different questions.
If question asks for one material give correct material not three possible alternatives of which one might be wrong. You will get 0 marks. This is particularly acute in plastics.
Examples need to be specific: Wood, metal, plastic unacceptable.
Learn elementary technical terms eg. ergonomics, anthropometrics, obsolescence, batch production.
Avoid bubble-charts and brainstorming.
Where you are offered two marks for a sketch, spend about three minutes producing a reasonable sketch. This is something you can practise, against the clock, at home. Sketching against time is important. Pencil sketch, not necessarily in colour.
Use annotation to explain technical detail.
Sketches are important tools to avoid generalised and unsupported answers.