First, slide the fabric cover onto the headband by placing the headband
into the one side of the fabric cover that has an opening.
Next, slide the plastic headband up to one side of the fabric inside
of the plastic casing by feeling it through the fabric.
Then put the whole headband in place on your head, while keeping that plastic band that is inside of the headband to the back of the fabric (toward the back of your head.) The fingers in this picture have the plastic headband pushed up against the side of the headband case.
This is where you want it.
Finally, tug down the fabric casing (not gripping the plastic headband inside) by both of your ears to make the fabric taunt and flat. This will give it the finished look we are going for.
Now you can look adorable all day long. By the way, if your headband starts to look wrinkly no matter how much you tug it by your ears, just iron the fabric casing and put it on again. It makes all the difference. And after wearing it many, many times, it just might need a good wash and ironing!