Re-tune the string, and then recheck the pitch of the 12th and 24th fret. Note how only the green light is illuminated, indicating that the pitch is now a G.

If the 12th and 24th fret are not in tune, repeat step 5 until they are in tune.

If the 12th and 24th fret are in tune, repeat steps 3 through 5 for each of your strings until each string is intonated.