Ask HN: Advice on mentoring a new employee/intern?

I'm sure many of you faced this situation before, but this is a first for me.

I've been assigned to mentor a new intern, for whom I have great hopes - This kid is sharp, a quick learner and has a bright future ahead.

My mentoring/teaching experience is limited to having been a TA in college, taught some courses, tutored some students and all that. Originally I majored in engineering, but got into programming after picking it up along the way. I still learn new things every day. Overall I have about 5-6 years of actual work experience in misc topics - web dev, databases, systems/ops eng., etc. I don't consider myself an expert on any of these.

So, I'm looking for advice, tips, shared experience on mentoring a new employee/intern from the good people who read this site. Common gotchas, things to avoid, things to emphasize, etc. Thanks!