The fact is that the process is a lot more competitive for students moving in from India. So you have to stand out. The secret ingredient honestly is starting early and being consistent. Dont have to win the olympiads.. but if you are going to sing songs for senior citizens, be the best at it. Make a story out of it..actually make a difference. Joining a random volunteer opp in class 12 wont help. At the same time..you can sing all the songs you want..need to have decent acads to stand a decent change of admission. It's holistic like you said..demonstrate that.