Viewers notice a teleprompter when the eyes chase text or the voice never changes pace. Both problems are solved before recording: by rewriting the script for speech and matching the scroll to your natural tempo.
Write for one breath
Break long sentences into spoken phrases. Keep one idea on screen at a time. If a line cannot be said comfortably in one breath, split it before you record.
Place text close to the lens
Keep the active line near the camera rather than in the middle of the screen. Increase the font until you can read without moving your eyes from side to side.
Let punctuation control the pace
Add line breaks where you want to pause and emphasize only the words that carry meaning. The scroll should follow your delivery; your delivery should never race the scroll.