you can summarize your past skills that are transferable to new career and link to your new career. Tell them how do you decided to go for the new career and what make you good at it. If you show the passion and drive to achieve a good, most employer will consider you a candidate.
Remember, show examples from your past experience that would demonstrate essential skills or characters that can be transferred into new career. This is the key. Passion is another key. The third key is confidence!
Good luck!