Hi, I'm currently in graduate school, and what has helped me write big assignments (not my thesis, at least not yet), but large assignments nonetheless, is setting a timer and committing a certain amount of time each day to complete work. I mean, after all, I wouldn't be in grad school if I weren't trying to improve some aspect of my skills that I don't have yet. So that's why I finally made the commitment to write for about 2 hours every day. It might be different for you, as for the amount of time you want to devote, and of course your process will likely be different than mine. But setting a timer and exclusively working on my papers for that period of time has really helped. It is good to simplify, especially in this world, when our lives are constantly being pulled in every different direction. Good luck!