The W3C's Web Content Accessibility Guidelines (WCAG) are the basis for many accessibility laws and more useful for actually learning what makes a site accessible.
If you don't already place an emphasis on using semantic HTML markup, learn more about that, it's the foundation of accessible design.
Sighted developers should use a screen reader on their own sites to get an idea of what's up. Very simple changes with semantic HTML can make a world of difference. It's sometimes as simple as swapping tags for their semantic counterparts.
If you don't already place an emphasis on using semantic HTML markup, learn more about that, it's the foundation of accessible design.