Just a note ... these crowns were pretty quick to make because I just used cardboard, but if you use sturdier materials, you will have a sturdier crown. But, this the kind of crown I would make for a "dress up" costume.
Below are the templates for these two crowns in Jpeg and Word. Please change the size so it works best for you or your Elsa.
I used card stock from the scrapbook isle at Joann's for one crown and cut up a gift box for the other one with added glitter. The scrapbook isle card stock was really too wimpy. I should have doubled it with something. So, I recommend you do, if that is what you end up using. The cup up gift box with glue and glitter was stronger. But consider other materials. I know one person used a quart yogurt container and cut the crown shape into it. So ... I'm just showing you one way to do this.
Now all the little tabs can be folded and the crown can be glued to a head band. I glued it on the bottom side, but it also could be glued on the top side. Does what works best for the headband you have. I found this easier to do if the headband was slightly stretched open, which I did by placing it around the little box I keep my embroidery thread in.
This style of crown might be easier to wear than the other, especially for a young girl.
BUT ... wait! I don't have a dress for this crown yet.
So that is what will be happening over the next three days, Snow Queen dress cutting, putting on the snowflakes and then sewing.