YAGNI. Following it strictly, following it mercilessly. Then follow the other user's answer about getting something working end-to-end first and fleshing it ou

YAGNI. Following it strictly, following it mercilessly. Then follow the other user's answer about getting something working end-to-end first and fleshing it out after that. These two things alone have helped me prototype things from ideation to working, testable project with almost a 100% success rate (even if the idea ended up being bad, of course). EDIT: Should expand on the "mercilessly" part. Even if you think you'll need a trivial, small abstraction five minutes from now, don't code it until it's blocking you. It seems extreme (well, it is part of the Extreme Programming principles) but it has granted me a 10x improvement in productivity as well as code quality after really committing to it.