How can I show a horizontally flipped copy of my Mac display on a teleprompter?

Stream the existing display to the teleprompter screen and enable horizontal flipping for that stream. You do not need a virtual screen when the desktop you want to show already exists on a physical display.

1. Connect the teleprompter screen as an extended display in macOS. For an iPad, connect it through Sidecar as an extended display. An HDMI monitor does not need Sidecar.
2. Grant BetterDisplay Screen Recording permission and enable Pro streaming features.
3. Open App Menu > [source display] > Stream Display. Choose the teleprompter screen as the target.
4. Select the stream’s horizontal-flip button—the icon with left/right arrows and opposing triangles. The receiving screen shows the flipped presentation. Your source desktop keeps its original orientation.

Choose the display containing your script as the source, and the teleprompter screen as the target. The target must not already be a macOS mirror target. A virtual screen is useful only if you want a separate desktop for the script while using your physical display for something else.

Use Stop Streaming in the source’s stream menu to end the presentation. If the pointer seems misaligned on the receiving screen, work on the source desktop or use the stream pointer actions. See Streaming for target selection and presentation options.