Listen to this loop: a kick, a clap and some hats. It sounds like one thing, but it's three parts stacked up, each playing its own pattern. Your song will work the same way. Right now it has your kick, and every part you add gets a lane of its own.

In a music program those lanes are called tracks. Ableton Live, the program pros use for this kind of music, shows a song as one track per part.