Publishing can be a strange industry to figure out because of all of its idiosyncrasies and I'd have been lost in my first year without a mentor. At Duckworth I've managed dozens of interns who are essential to any publishing house and if there's one piece of advice I can give it's this: never accept an un-paid internship! The publisher may be offering you experience but the work you do has value.
Now that I've been in the business several years, I always make time to mentor one or two people at a time who are either trying to get their first job in publishing or want to get their next job in the industry. I've acted as a mentor for the Society of Young Publishers and for UCL's Publishing Masters programme. It's always been a rewarding experience and once the mentoring period is complete, I love reconnecting with mentees to learn of the progress they're making in their careers.