Help creating and writing an access policy for an animation project

I'm involved in an animation project. Need help devising an access policy for a captioning plan (e.g. captions, transcripts and audio description). The animation will be about ability/disability (physical and mental) and the way these are portrayed in the media. The animation will be shown in the UK and China so need to cover access in both countries.

If you have some experience with this, please contact me to discuss and with any questions. Thanks