As soon as you press the flag button, it generates 10 basic notes. It'll probably sound bad at first, and if it does, just say it sounds bad. It'll alter the notes slightly in a random pattern. Then you judge how it sounds once more. Once it sounds sufficient, you can set it to repeat, or continue to change it. This is still a work in progress, so check for any updates later on.
Small inspiration from carykh on youtube.