Preparation: The more research you do to find out about employers, their recruitment process and the industry, the better prepared you'll be to make the choices affecting the next 5 to 10 years of your life.
Understanding employers: You need to understand what the employer is looking for and show them up front that you have it. In a pile of hundreds of applications, they are going to pass by vague or general ones, and head toward the ones that clearly have what they seek. The goal of every employer is simply to find the candidate that will be the best fit for their particular situation.
Now it is time to start matching examples of your experiences to what matters to the employer. You can use examples from part-time work, extra-curricular activities, volunteer work, or university projects to demonstrate that you have what they value in an employee.
The organisation has put each question there for a reason, and often also a word limit, so don't make the mistake of skipping questions or rushing off an answer because it doesn't seem like an important question.
Take your time when answering, preferably, get the questions, and go away from the computer. Then:
Once you are satisfied you have prepared your application thoroughly, re-enter the online system: