How much of my personal statement should I dedicate to extra-curricular activities such as sport and volunteering?

A sensible approach would be to offer around 30% of your personal statement to extra-curricular activities. However, this answer varies depending on which universities you are applying to. For example, Oxford and Cambridge prefer you to focus on academia rather than extra curricular activities, and therefore if you apply there you may only have around 20% of your personal statement detailing your extra curricular work. More importantly, your shouldn't just list your hobbies in your personal statement but describe why they are beneficial to your course. For instance, if you enjoy playing hockey and volunteering for a local charity, this demonstrates your ability to work in a team and manage your time effectively - both of which are traits that would be beneficial to your chosen subject.