I've attached a template that we use at my current work to help our administrative and program design staff to ensure that they share all of the relevant information about a new/custom program with guides who are delivering the program. It's a little bit context specific for our business, and it's certainly not perfect, but it provides a useful template to start from.
(This template assumes: 1) that the program is embedded in our broader operating systems and processes, and 2) that a person has already been onboarded into our business and knows our foundational ways of working. This template is just about the custom program and information that is unique to that.)
Sometimes the document we give to staff is only a page long (like when it's a variation on a normal product we do and lots of the headings are irrelevant), and sometimes it is a massive volume (like when we're delivering a fully customised multi day day program). And sometimes rather than writing out all of this information, we might make a simple video for staff to watch including whiteboard sketches and mad arm waving to convey important points.
Feel free to adapt and use this template in your work. (And as always, please share suggested improvements).