I often hear from academics who are frustrated because they think they need large blocks of time to move writing projects forward, and during busy teaching semesters large blocks of time are few and far between. People are often surprised to find to find that they CAN move their research forward in very short sessions. Some tasks may not be able to be done in small blocks – so identify those that can. Can you read for twenty minutes? Work on the bibliography? Find a citation? Clarify one point?
Take out your calendar right now and find five twenty-minute periods and block them off. Keep a log of the number of times in the week that you seize a small block of time for writing. The minutes will accumulate into additional hours spent on your article or book, and keeping your head in the project in those short sessions will mean less ramp-up time and faster progress when a larger block opens up.