In addition to my own advice for faculty mentors, here are some recent posts on mentoring at every level of the academic system:
“‘I Just Do It’: Mentoring & Honoring our Undergraduates” by Trina Smith
“The Top Five Traits of the Worst Advisors” by Karen Kelsky
“Faculty Mentoring Faculty: Relationships that Work” by Maryellen Weimer
The first and third are from the perspective of the mentor while the second focuses on the perspective of the mentee (similar to my post on mentors and anti-mentors), though that can also be helpful for mentors who are trying to avoid screwing things up.
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