Inspiration is like fresh produce. It's best if you get to it as soon as possible. If you put it aside for three days, it might not be worth anything by the time you get back to it.
If your schedule is perpetually jammed, so that you never have time to follow up on inspiration, you're missing out on the best things in your life. Working hard all the time will not make you successful, but inspiration will. Make room in your life for it. And when it shows up, be ready.
"Inspiration is a now thing. If it grabs you, grab it right back and put it to work." — Jason Fried and David Heinemeier Hansson, Rework.