The content on your website should be simple and easy to read so a wide variety of users can enjoy your copy.
If there is video or audio content on your website, there should also be a transcript.
Be sure to design ALL your forms with accessibility in mind. Label all fields on your forms.
Provide plenty of space between blocks of text for people that have trouble tracking text.
Minimize having links open in new windows, as it can be confusing to users.