@hampshire It’s going to be difficult, while extra-curriculars are quite useful, banks want to see some work experience especially for grad roles. You’re up against the usual lot, oxbridge grads with goldman, morgan stanley internships so the competition is incredibly tough. If you live in London, unpaid internships are your best bet, and start approaching boutiques. You could also try for some off-cycle internships, I think Citi has one starting February for their investment banking department.
But to be blunt, if you want to get into the bulge brackets, there’s very little chance of getting an interview for a grad analyst position without any experience.