Making crowns is a time-honored arts and crafts project. There are many different ways that you can do this. Here is a simple method:
White poster board-long
Cut a strip of poster paper approx. 1-1/2″ wide, and about 28″ long.
Wrap the strip around child’s head to make a circle. Trim to fit. This will the headband base for the crown, but don’t tape it shut yet. Take it off child’s head.
Cut the crown part next, then tape (or glue or staple) it to the band.
Brush white glue on what will be the outside of the headband and crown, and cover with glitter or tissue paper. Or, just color with markers and crayons.
When crown is dry, wrap it again around the child’s head and tape in place to fit.