The NumFOCUS DISCOVER Cookbook (Diverse & Inclusive Spaces and Conferences: Overall Vision and Essential Resources). A guide for organizing more diverse and inclusive events and conferences, produced by the NumFOCUS Diversity & Inclusion in Scientific Computing (DISC) Program, with support from the Moore Foundation.
https://reachwater.org.uk/wp-content/uploads/2019/05/2019_05_22_Inclusive-Conference-Guide.pdf
Just came across this one today.