@azzoor has this great video with some advice on how to set up your device for testing accessibility and a ton of tips will get you testing effectively in no time.
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If, for some reason, you are creating a button from scratch, instead of relying on UIButton (perhaps you are adding a fancy micro interaction animation?), take into account that you’ll need to configure the button accessibility trait.

Anything representing a heading in the app should have the header trait. It allows for a faster way of exploring a screen and jumping to the part of the app you are interested in. Screens should also start with a header.

With accessibilityRepresentation(representation:), you can create a custom component and it can be perceived by assistive technologies as the view you pass as representation. No need to manually configure accessibility attributes. It is one of the most interesting additions to SwiftUI to help you develop accessible UI components. If your custom component behaves similarly to a native one, this is the way to go. https://developer.apple.com/documentation/swiftui/view/accessibilityrepresentation(representation:)