1. A computer-implemented method comprising: displaying, on a display device, display content representative of a temporal transition of a music performance; recording input audio; receiving, during recording of the input audio, a first user input designating a desired time position on the display content displayed on the display device; and storing, into a storage device, a recording time of the input audio based on a time point at which the first user input has been received and the time position on the display content designated by the first user input, in association with each other.