@Robertovna you can place the single strings right inside the loop with the other strings so they're slightly overlapped (and on the correct side of the pattern) then knot over the length of the loop as usual. Before starting the pattern, gently pull the single strings through the loop, and the tail ends will disappear inside the loop, just be careful for the first knots so you don't accidentally pull them all the way out. You can also search YouTube for a video by Empatheo called "Teardrop Loop While All Strings Are Different Colors" 🙂