Download this printable crown from primecp for a fun New Year's Eve prop. Then just cut and paste together to fit any size head.
Good for ages 6 and up.
Get the template here:
https://content.primecp.com/master_images/AllFreeKidsCrafts/Happy-New-Year-Printable-Crown.pdf
Finley and oliver has a felt hat tutorial using toilet paper rolls, felt and ribbon.
Get the instructions here:
http://www.finleyandoliver.com/2012/02/diy-mini-crowns.html