Dr. Robert Thach
Dean of Arts & Sciences
Washington University-St. Louis
Academic discipline, of course, makes a great deal of difference: students in the natural sciences generally have a much easier time of it than students in the social sciences or humanities. The major reason for this, in our experience at Washington University, is the different ways these students are supported, both financially and intellectually.
So, the advice I would give to students in areas outside of the natural sciences is not try to hold down a full-time job while writing the dissertation. A TA-ship is much better, as these are normally half-time jobs. Even better, of course, is a Fellowship.
Even if one is lucky enough to not have to work at all while trying to write, it is still very important to stay connected with both Advisors and peers, and the academy in general. Go to seminars; join dissertation work groups; go to lectures. These activities will keep the mind active, in ways that selling widgets may not.
In addition, structuring the day is very important: most successful writers in any field plan to write something every day, even if they don't feel like it. Imposing this kind of discipline on oneself pays off hugely in the long run.