We all struggle with this problem, to a greater or lesser degree. One solution is to keep your work in manageable chunks. Another is to develop a habit of compl

We all struggle with this problem, to a greater or lesser degree. One solution is to keep your work in manageable chunks. Another is to develop a habit of completion. Another is using a task management system religiously. Another is to have structure imposed on you externally (the day job is a classic way to do that). I often say "Finished is better than perfect, always." It's a reminder to me as well as to the people I try to help with it. One of the biggest struggles is with multitasking. Don't do that, if you can avoid it. Work on one thing at a time. The Pomodoro technique helps in keeping focus, I think.