which extra-curricular activities shall I include in my PS?

This is a very important question to answer as it requires a lot of thinking, different variables and drafting so I will answer this in part and the rest is dependent on your unique circumstances so I will invite you to book a tutorial.

WHAT IS EC?

Extra-curricular (EC) activities can be anything and everything which falls outside your course syllabus/ curriculum. 

However, there are some forms of EC that may 'look better' or give off a better impression of you as a person and your reasons for applying for a particular course. But there is a way around that which will be discussed now.

THE TRICK/

Now it's up to you to pick whatever EC you want and this can be a sport, an obscure hobby (i.e. stamp collecting, busking, fashion designing but you're not a fashion student) or something related to your course (volunteering in a hospital ward / applying for a medical related subject or writes blog posts/ English).

so this can be whatever you like and aim for a mixture of things, so for example a sport, something obvious and something unique but there is a catch.

And the catch is that you have to make it link to your course or to yourself. linking it to your course is easy enough to understand but what I mean by to yourself is, it has to show how that hobby or EC has improved you or has sparked something in you to which you then are driven to build upon by doing other things and one may be to study it in further depth at Undergraduate level.

EXAMPLE/

SPORT > Tae Kwon Do = developed interest in different Cultures and martial arts

>> Thai boxing = explored different forms of martial arts because of TKD. By studying these martial arts I have learnt why they were invented and how they were developed. 

>> has peaked my interest into the History of different cultures that are not in the Western World, etc. and then you can add an interesting point which will make everything tie and relevant

you DO NOT want to add EC just for the sake of adding EC. Listing is a no-no nor is just simply stating that you do the karaoke every weekend. I could go on but...

Book a tutorial for an expansion on the ideas explored here and more in depth session as well as tailored advice!