If you aren’t already aware of the Web Content Accessibility Guidelines (WCAG), there’s no better time than the present to get started. WCAG is a central element of a series of web accessibility guidelines published by the Web Accessibility Initiative of the World Wide Web Consortium (W3C), the main international standards organization for the Internet.
In English, these are the standards that let people with disabilities interact with your online content. As of now, WCAG compliance is not required on any national level, but that could change. You can prevent getting blindsided by regulations by starting the review and modification process now, so changes can then be rolled out in stages.
One of the best places to begin that you can do first hand, is begin checking color contrast for fundamental web content like font, link, and button colors.
In order to help you get started, I published an article at ArtsHacker.com that provides step-by-step instructions along with online resources you can use.