Doesn't take too long, and especially great if you like tedious work.
Stuff you need:
Thread (optional - 2 colors)
Felt - 2 colors
Sewing machine (optional)
Step 1: Measuring And Cutting The Fabric
For the fabric itself - I think a medium weight fabric would work best. Different colors could also work.
Step 2: Sawing The Scarf
Then, turn the scarf inside-out. Connect each pair of wires together, and also fold their edges inside, to avoid punching through the fabric. Then insert the wires. I used two wires on each side. They would let you shape the edges of your scarf nicely. It's better to sew them in, so that they don't move around inside. You can use either zig-zag or some other wide stitch. I thought that's a great opportunity to use the not so useful star stitch.
Afterwards sew the gap on the right side.
I wanted to add two yellow lines, but only from one side. I used an upper red thread and a lower yellow thread. If your sewing machine is well balanced you'll only see one color on each side.