This study examined the efficacy of a novel manualized educator training as part of the Guggenheim Museum's Guggenheim for All (GFA) program to increase access to high-quality arts programming for neurodiverse individuals. Ten arts educators and 37 parents of autistic children aged 2-17 were recruited to participate in this study. Results demonstrated that the training program significantly improved educator fidelity in implementing evidence-based practices in virtual art classes for autistic individuals, as well as parent-reported sensitivity of the educator to their child's individual needs. While the manualized training encompassed several domains, the use of visual supports, in particular, showed the greatest improvement amongst educators following the training program. Overall, this study provides evidence for a manualized training program for arts educators that will increase the use of evidence-based practices in arts programing for neurodiverse populations.