Must do adequate research of J.P. Morgan as a business, use your own personal experience to answer questions. ie. take examples from jobs where you've previously worked, University assignments. Think about what kind of questions you will get.
Look for all possible ways to get experience in the firm, it offers more than one route such as the Hatch program and High school programs
Technical knowledge is necessary but not sufficient - you just need to know them. I feel that people get too bogged down in this part of the interview process. It's the behavioral part in interviews that is more important. Be likeable, be interesting, show integrity, show interest in the role.
Prepare in depth knowledge on standard investment banking interview questions and brush up on corporate finance
Research the company in depth. J.P. Morgan prides itself on their history and culture so understand how this aligns with your values and be able to detail this in the interview.