Locate a music composition package called Instant Music for the C64. Online auction sites and C64 message boards frequently include advertisements for Instant Music and other C64 music composition packages with the original box and instructions. If you are unable to locate the original version, c64music.blogspot.com has it available for download (see References).
Load the Instant Music disk on your C64. After it loads, click the drum, guitar, or bass button on the bottom of the screen to select which instrument you would like to be active.
Press and hold down the mouse button in the note area above the instrument boxes in order to create the notes in the composition. If you make a mistake, you may click "Edit" and choose a delete option from the title bar at the top of the screen.
Click "File" on the title bar, then select the appropriate option to save the composition. Click "Jam" on the title bar to access playback features.