Some advice on the subject can be found in the article by Richard Reis and in the book by Steven G. Krantz (the second link is from the discussion of the Secret Blogging Seminar’s post on the subject). As for the letters of recommendation for students, see also here, here and here.
This is a series of four articles at Inside Higher Ed by David E. Drew and Paul Gray:
These authors have also recently published a book on the subject but I haven’t got it yet.
However, I’ve just found a presentation which appears to be a nice summary of the book (important note: the link in this paragraph works even though Snapshots says it doesn’t!).
S. Weinberg: Scientist: Four golden lessons
R.P. Feynman: A Letter to a Former Student
J.D. Watson: Succeeding in Science: Some Rules of Thumb
(see also his book Avoid Boring People)
A. Ciechanover: Nuggets of Career Advice
The above materials make for an interesting comparison with the advice from the Fields medal winner Terence Tao.