Alternate chords are the small chords above the Regular chords. Switch to Alternate Chords then input chords as usual. To delete, add, modify, change to Alternative chords again.
Note: the Player will ignore the alternate chords (they are used for visual purposes only) but will transpose along with the main chords.
Example:

- Android, iOS
- Windows, Mac
Android, iOS
Tap this small button to the left of the chord box at the top of the editor keyboard
Windows, Mac
Click on Alternate Chord button near the Chord input box