Gather your materials (I didn't use some of them):
1. 2 metal / plastic headbands
3. glue (I used super glue but I don't recommend it)
5. tape measure
Measure the length of the head and cut 2 strips of fabric with the same length and a width that is wide enough to wrap around the headband but narrow enough so it wont be seen.
Wrap the fabric on the headband. I used super glue but I like I've said, I don't recommend it. You can use any fabric glue or whatever. But if you insist on using super glue, be careful not to put too much as it will bleed on the fabric.
Do it again on the second headband.
Now, glue the ends together and leave a gap between the headbands like in the picture.
Get another strip of fabric, fold it (with the wrong side on the outside) and sew it. Once done sewing, turn it inside out, twist it and wrap it around the headband.
Glue the end of the fabric to the ends of the headband. Glue what you think needs to be glued, and you're done!
Hope it'd be easy for you to understand and don't hesitate to ask questions! :)