What’s the best way for me to personalize the dictation with Siri so I can automate my input given my need for dyslexia accommodation and multitasking.

After you set up iPhone, you can adjust accessibility settings.

• Go to Settings > Accessibility.
• Choose any of the following features: Vision. VoiceOver. Zoom. Display and text size. Motion. Spoken content. Audio descriptions. Physical and motor. AssistiveTouch. Touch accommodations. Back tap. Reachability. Call audio routing.

Get started with accessibility features on iPhone - Apple Support

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