Always keep the end game in mind and put in place a process where you are consistently asking yourself how what you are doing is getting you there. If you decide to go down the rabbit hole anyway, you have to admit to yourself that you are procrastinating rather than solving problems. This works for me, and I am 2-3x more productive. As soon as I get distracted, like right now, I know that I am wasting time writing a post on HN rather than attacking my goal.