I have written before about how holding back the writing stage can actually make writing easier. Still, even a well-organized and well-planned paper needs to be written in the end. Here’s one thing that can help in that final stage: setting a timer. Popularized as the Pomodoro technique, the idea is to set a fixed time during which you write, say 20 minutes. The trick is to write exactly 20 minutes, and then stop. During these 20 minutes you do nothing else. The intuition is that because the task is limited, it’s easier to fend off these procrastinating thoughts like checking e-mails. It’s also important to stop after 20 minutes (or whatever time you decide) to keep the momentum. Actually, it’s probably better to start with a relatively short time and increase it gradually than jumping in with a number found somewhere (25 seems to be one such number). It always baffled me why a tomato-shaped kitchen timer should be preferred by so many when any timer or clock does the work.
Such boost of focused work can also be used for other tasks. I sometimes use a timer set to 10 minutes to get started with some tasks, for other kinds I use longer periods.