I have two times when I write: in the morning when I'm commuting and in the evening just before heading to bed. I think over 90 percent of my posts are written on either of those times.
Those are easy times to write for me, I have so accustomed to writing routinely in those situations that I have found myself accidentally almost starting to write in similar situations. For example sitting down on a train, just like I usually do in the morning when I commute. The cue to start writing is so strong I don't even have to think about it.
They are so strong that it's not just starting to write on those situations, but actually holding me back writing in other situations. Trying to do so I just find myself thinking this is not the correct time. Even though I know it would be better to write now than wait until it is the correct time. I just keep postponing it.
I really need to make some real conscious effort to overcome those "I can't write right now" feelings. I'm too accustomed to doing things in a certain way it feels difficult to do it any other way.