How it works is the person above you gives you a song, and you rate that song and give it to the next person. Example:
Person1: 5/10, Watcha say, Jason Derulo Person2: 6/10, Dark Horse, Katy Perry
6/10 was Person2's rating of Watcha say by Jason Derulo, then Person2 gave a song which the next person would give their rating and a song, and so on.
I'll go first:
Ride, Twenty-One Pilots