The work of graduate school, ostensibly at least, is the completion of a course of study, which, following classroom time (mostly covered in other entries) comes to a climax in a series of hoops: a qualifying exam, maybe a prospectus defense, a dissertation. Some advice on those processes:
First, Psyc Girl asks about tips on studying for comps, and gets some good feedback in the comments.
Of the entire process, much has been said about working with advisors, and while other great posts on the topic certainly exist, some excellent nuggets of wisdom can be found here:
Claire Potter at Tenured Radical considers the virtues of the "good-enough advisor".
Undine at Not of General Interest has a bit of a cautionary tale about how much power advisors do and don't have.
Meanwhile, Dr. Crazy at Reassigned Time considers the role of mentoring more broadly.
Of course, one must also consider research and writing processes, and Undine offers some fantastic advice on researching, while EA at The Grand Improvisation rants usefully about her own processes.
Finally, while many have written on the writing process itself, few do so as eloquently as WWWMama at Working, Writing, Wailing Mama. Here are three posts that give glimpses into the dissertating life.