Here is what he says about not letting a moment of inspiration go to waste:
On YouTube there’s a documentary about Serling made after his death. The narrator reading Serling’s words is a sound-alike, which is a little creepy, but there are some fascinating interviews with other pioneers of early television, as well as his wife.
Here’s a link to part 2 (about 8 minutes long) of the 90-minute documentary—the part in which they talk about live television and Serling’s first success and the pressure it created for him. It features clips from the live broadcast of “Patterns” and also “Requiem for a Heavyweight,” which won 5 Emmys including one for Serling. One of the things he talks about is writing “not about the morality of right and wrong, but morality on the shady site of the street.”
I recommend going to YouTube and watching all the parts if you have the time The title is ‘Rod Serling Documentary.’ The program tells you a lot about Rod Serling, including his guilt about “going Hollywood” (which he reflected in his script, “The Velvet Alley”). It also reveals much about the early and later days of television and the origins of “The Twilight Zone." Commenting on the censorship that affected his earlier dramas, he said, “On the Twilight Zone I knew that I could get away with Martians saying things that Republicans and Democrats couldn’t.”
Of the 100 scripts in the first 3 seasons, Serling wrote 70. He said, “Each 'Twilight' script takes me 35 to 40 hours. It's the kind of schedule that if I drop a pencil and then bend over to pick it up, I'm two weeks behind."
(Want to write your own scripts or books? See my book, "Your Writing Coach," published by Nicholas Brealey and available from Amazon and other online and offline retailers. Specifically for scripts, see if you can find a copy of "Successful Scriptwriting," by me and my friend and colleague, Kerry Cox. It's out of print but the concepts and methods in it are still valid.)