The same general guidelines that help make webpages and Word documents accessible should also apply to OER. For videos and visual materials, it is important to provide a transcript or alternative text for description of the object. Simply formatting your content in a logical way can also help make it more readable by assistive technology software and easier to read for everyone. Google support has provided a great list of best practices for making your document or presentation more accessible.
After implementing these guidelines, always run your presentation through an accessibility checker on various computers and mobile devices. This will tell you, for instance, if the text contrast on your resource passes the ADA accessibility standards. If possible, have people with disabilities test your documents. Here is a list of free tools for checking the accessibility of various documents:
Accessibility within Open Educational Resources and Practices for Disabled Learners: A Systematic Literature Review by 