How do I keep vendor coordination from overwhelming me?

When coordinating vendors overwhelms you and things fall through, the problem is usually not effort. It is that you are trying to hold too many moving pieces in your head at once, and the head is a poor place to store them. Things fall because nothing is catching them. Get it all out of your mind and into one place you trust. A single list: who owes what, by when, and where each thing stands. When it lives on paper or a screen instead of your memory, the panic drops, because you can see the whole board instead of fearing what you forgot. Most things fall through cracks that only existed in your head. Then work it in small, steady passes. Check the list each morning, chase what is due, update what moved. You do not need to track everything at once; you need one reliable system and the habit of tending it. Overwhelm comes from juggling. Relief comes from putting the balls down somewhere you can see them.