Ensuring accessible experience for Switch-and-Puff users, from https://axesslab.com/switches/
Make your interface keyboard accessible. That is, make sure you can control it only using the tab, space and arrow keys of your keyboard. If that doesn’t work, then switch users most likely will run into trouble.
Place key information, buttons and links “above the fold” – visible without scrolling. Scrolling usually requires a lot more time and effort for switch users. With iOS Switch Control, a user needs to activate the switch seven times to scroll: 2 clicks to see the interaction menu, 3 clicks to navigate and activate the scroll and 2 clicks to remove the menu.
Don’t require hover, click-and-drag or other advanced gestures. Although most switch interfaces have functionality for these gestures, they take a lot of effort to carry out and many less tech-savvy users will not know about them.
Use a large text size as default. Many switch control users physically can’t lean close to a screen to read tiny, italics text.
Avoid time limits. It will take most switch control users longer to complete a form or navigate your interface. So avoid using time limits. But if you do, make sure to give the user a way of increasing the time and give them a warning long before time’s up.