I'm sure everyone's already seen this, but via Leiter, here's Aidan McGlynn's handy roundup of publishing advice for grad students in philosophy. As someone who's gotten astonishingly shitty advice about this in the past, it really is useful to see the thoughts of people who aren't evil freaks.
There's one thing about publishing I wish someone told me back when I was starting my dissertation. Obviously, I don't have a whole lot of experience publishing, so take this for what it's worth. But I wish someone had told me not to think of what I was writing as a chapter. It wouldn't make sense to think about it as a stand-alone paper, either. I wish someone had told me to think about what I was writing as neither a chapter or paper, but work. Because the work is going to be the basis for both a chapter and a paper. I wish I was thinking like that, because then I'd have been thinking about how the work would have to be packaged to be a chapter and how it'd have to packaged to be a paper. It seems like that could have saved a lot of pain in figuring out how to rewrite a chapter as a stand-alone paper.
Anyway, I wish somebody had told me that.