The work is not but many things around it can be. Setting a daily schedule, always get a cup of tea/coffee, sit here, play this music, create a log entry, etc etc. Can all help put the brain in "oh it's time to work" mode.

The pomodoro process works for me and for a lot of people. Just set a timer for 25 or 30 minutes and make a rule you can't do anything else until the time is up. Just sit there and do nothing if your brain refuses to cooperate. Eventually boredom will do the trick.

Finally, creative work often involves lots of bits that aren't really creative. Source control, editing, issue trackers, etc. You can gain a lot by setting up a strict, thoughtless way of going through these motions. Makes it painless and not a hurdle, eventually, even if it still eats time.