You’ll never feel ready. Readiness shows up about halfway through the first attempt.

Readiness is not a state you reach before acting. It is something the acting produces, which means waiting for it puts the two in the wrong order. What you feel beforehand is mostly the cost of uncertainty, and the only thing that reliably lowers it is information you cannot get without beginning.

Make the start smaller instead of waiting for the feeling to change. Choose the first twenty minutes of the thing rather than the thing, and check how you feel once you are inside it.