5 Ways to Ensure Accessibility
Pure HTML - validate against a W3C spec
Don't rely on fonts or color to communicate
Structure tables carefully
WAI page authoring guidelines
Notes:
1. Use only attributes that are supported by one of the W3C specifications (HTML 3.2, HTML 4.0, or CSS) and validate your HTML against a W3C DTD.
2. Always provide descriptive ALT tags for graphics (especially images used as submit buttons), applets, imagemaps, and links (including all links within an imagemap).
3. Avoid the use of fonts or color as the exclusive device for establishing hierarchy. Wherever possible, use HTML heading levels (<H2>, <H3>) and definition lists to describe the structure and relationships of information.
4. Structure tables so that they can be interpreted by screen readers and/or provide an alternately formatted (accessible) version of the information.
5. Make sure that pages using newer technologies (frames, scripts, style sheets, applets, forms and tables) fail gracefully (i.e., do not leave a user "stranded").
6. Read and follow the WAI page authoring guidelines