One of the main reasons for irrelevant, repetitive or unclear ideas in task 2 essays is that candidates do not think enough about the subject matter of the question. 

Most task 2 questions are based on the everyday experience of people e.g. going to university, raising children, travelling to work. 

So when you start planning your ideas in those first 10 minutes before you start writing, put yourself in the shoes of the people who have a strong interest in the topic and who have to make wise, balanced decisions. Some examples: 

employers, commuters, parents, factory managers, government ministers or advisers. 

For example: whose shoes could you put yourself in, for this question:

Some people believe that schools should choose students according to their abilities, while other people think students with different abilities should learn together. Discuss both views and give your opinion. [scroll down for answer]

My answer: senior teachers, parents, children, government ministers.