Ages ago now, I got some new headphones because mine broke, as they do now and again. My old ones were pretty pastel colours, and the cables were light blue with little hearts on them, and they were generally delightful. My new ones are black. This was a big disappointment to me, even though the quality of the headphones is good. But! I was looking at things on the internet the other day, and I saw someone had wrapped theirs, and I did the same.
It's a basic macrame/friendship bracelet knot, with the cord as the 'lazy' thread and embroidery thread or similar as the working thread. My stripy one was done with a colour-changing thread, though you could just as well do stripes the old-fashioned way. This was me doing it on the train (which intrigued my fellow passengers):
And here's the finished headphones:
Supposedly it also stops them from tangling, though I'm not sure that's actually true.