You need a plan, not a novel. A plan forces you to test your assumptions on paper before you burn cash proving them wrong. Think of it as a living tool, not a document you file and forget.
It is ready when it survives a skeptic. If a smart outsider can grasp the opportunity, the risk, the economics, and the ask without a twenty-minute explanation, you are close. If you spend most of the time explaining the product instead of the business, you are not.
Clear thinking and a believable path to returns. The bar moved: they want to see how you survive the next eighteen months, not only how you conquer the world in ten years. Inflated projections now work against you.
That is the best time. Waiting until the pitch is tomorrow means we manage a crisis instead of building the story. We settle the business logic first, and the pitch comes out of it.