When you were a kid, did you ever have an idea that made complete sense in your head but as soon as you told your parents (or the cops) how you came up with that sound-proof plan, it didn’t seem so logical anymore?
Being in your own head can be a dangerous place to be. So when an idea hits, say it out loud. Write it down. Look at the words in front of you. Then ask yourself, how does it sound now?
This isn’t to say stop visualizing, stop dreaming. Keep doing those things. When something brilliant surfaces and starts to take shape in your mind, before you take the next step, say it out loud, write it down, and look at the words. If it passes the eye (and ear) test, then don’t delay, start doing.
You won’t know for sure if it’s a good idea until you begin executing it. But if it passed your say-it-out-loud test, then you can be certain it’s good enough to try.