While "you are what you eat" has become an almost meaningless cliche, its truth is undeniable. The substance of your body is made up of the food you eat. Let me add another aphorism to your arsenal.
You create what you consume.
What you create is a direct reflection of what you choose to expose yourself to. This is not to say that you create exactly what you take in, although that certainly happens occasionally. No, everything you put in your brain is reflected through the prism of your own unique point of view and experiences.
While it is a given that an athlete should change their diet while training for a big event, why don't creative people do the same thing? Martin Scorsese shows his actors many movies before he starts filming as a way to make sure they are all on the same creative page. As Winona Ryder said in Harper's Bazaar:
He would show us films in the screening room in his brownstone, and I don't know if he realized it, but he was basically narrating the entire film. We'd be like, "I wonder why he's showing us this film?" but it would be for one shot or one scene—and it was like a four-hour epic!
Stephen King said in his excellent book On Writing, "If you don't have time to read, you don't have the time (or the tools) to write. Simple as that."
Before you embark on a new project, give some thought to changing your cultural diet: read the books, have conversations with relevant people, see the movies, go to plays and museums. Immerse yourself in the world you want to create. Go into training to complete the creative marathon you want to undertake!