Strings are what the beads bounce off. Tilt sets pitch. A string rising to the right sings higher, one falling to the right sings lower, and flat strings sit in the middle. Short strings jump up an octave and long ones drop down. Every note stays in your key and scale, so nothing sounds wrong.
Spouts drop beads in time with the tempo. Click a spout with the spout tool to cycle its rhythm, or drag it to move it.
Each string plays the instrument that was picked when you drew it. Beads pick up the color of the last string they hit, and that's what the weave is made of.
Hold Shift while drawing to snap to 15° angles.