Without a plan, I often find my day goes marginally well. Since there was no plan, I did not succeed or fail. But I didn't move many of my creative chess pieces forward on the board either.
Don't let a single idea pass unnoticed. If you can capture the essence of the idea in some form, some shorthand version of your vision, then capture it. If you can stop everything else you are doing and allow the creative gift to come through you, do it. Stop. Listen. Create.