Best thing in my opinion is to have something external that limits your schedule.
For me and few it of my coworkers it definitely were our children. I know I want to be at home by 18:00, so that I can have dinner with my family. One colleague was starting at 7:00 and and finished by 15:00, because he was pisking up his kid from preschool at 15:30 most days :)
I am not suggesting for you to get a kid :P but knowing that every day I want to end by $HOUR because I have a $THING does wonders :-)
For me and few it of my coworkers it definitely were our children. I know I want to be at home by 18:00, so that I can have dinner with my family. One colleague was starting at 7:00 and and finished by 15:00, because he was pisking up his kid from preschool at 15:30 most days :)
I am not suggesting for you to get a kid :P but knowing that every day I want to end by $HOUR because I have a $THING does wonders :-)