It a simple message really.
1. A daily goal sheet and tracker you can use to track your progress each day.
Experiment with this. I use steno book. One page a day. I’ve tried other methods most of them more complicated but they don’t work for me. You want something simple you use everyday.
2. Set rules to operate your day by: example check emails only at specific preset times.
3. Schedule and take breaks, it’s part of being disciplined.