Designers can help increase the accessibility of web-based content by providing supplementary and alternative ways of interacting with the information, as well as making sure that assistive technology and tools can accurately and effectively convey the information to the user.  

Some methods of achieving this include:  

Text Alternatives and Supplementary Materials: Add alternative (alt) text to images, transcripts for audio, and captions for videos to ensure all users can access content in different formats.

Adaptable Layouts and Content: Add text that explains the relationship between two elements and refer to components of a page with a combination of traits to make it easier for users to navigate and interact with the content.
Present the order the information is introduced in such a way that allows assistive technology to accurately relay the information to the user. Structure a webpage to work with both landscape and portrait orientation also help with making a site more accessible. 

Text Characteristics, Volume Control, and Color: Use text instead of images of text whenever possible, and allow the size and spacing of text to be adjusted to fit user needs without losing content or functionality. For content with audio that lasts longer than 3 seconds, include a way to pause/stop it and adjust the volume. Follow the contrast requirements for adjacent colors, text, and images of text. Refer to this link to check the contrast of your website elements. 

It is essential to make websites both easy to navigate and safe to use, with or without assistive tecnology.  

Some methods of achieving this include:  

Keyboard Compatibility: Make sites responsive to standard keyboard shortcuts, and make them remappable to allow use with or without assistive technology. Code for a mode of operation where a keyboard focus indicator is visible on the screen. 

Time Limits and Element Hiding: For elements with non-essential time limits, allow the user to adjust or extend the time limit to give them enough time to use and read the content on a page. For elements that move, blink, or scroll, provide an option for users to pause, stop, or hide the information unless it is essential to function of the site. 

Prevent Seizures and Physical Reactions: Never design content in a way that is known to cause seizures or physical reactions and take into consideration the general flash and red flash thresholds.

Navigating the Page: Keep pages well-organized with titles, headings, and labels that describe the content. Provide at least two ways for users to get to a subpage.  

Other Inputs: For touchscreen-based content, use touch gestures that can be completed with one finger, or add alternative ways to accomplish the same motion. Make functions cancelable and allow users to trigger functionalities with speech activation. Do not rely solely on a device being moved in a specific way to control the page content (unless it is necessary) to account for users with unsteady hands.

Making webpages easy to understand and interact with is essential to any user experience, especially for people who rely on assistive technology. Consistent navigation methods, language identification, and error detection are important elements to consider when designing a website. 

Some methods of achieving this include:  

Make Content Readable: Make sure the language your webpage is written in can be detected, read, and translated by assistive technology. 

Keep Things Predictable: Do not change the context of webpage elements when interacted with or change the settings of the UI without warning. Make icons mean the same thing across all pages and keep navigation menus and functions consistent. 

Check for Errors: When a user makes an input error, make that error obvious through text and suggest ways for the user to fix it. Label fields that require user input, and allow input submissions to be either reversible, reviewed by the user before submitting, and/or confirmed before submitting. 

The visual elements of a page and assistive technology’s ability to interact with it also rely on proper coding. Making sure your code is clean and compatible is just as essential to a user’s experience as proper text contrast or accessible touch gestures. 

Some methods of achieving this include:  

Parsing: Nest coded elements properly and use the correct tags to avoid confusion from assistive technologies. 

Names, Roles, and Values: Make the name and role of all UI components detectable to assistive technologies and convey them to the user. Notify the user of any changes they make to the state, properties, of values of the elements on the page. Click here for a list of techniques to successfully accomplish this criterion. 

Status Messages: Notify users of important changes in the content or status of a page, and make it detectable to assistive technologies.