Urgent - How to make a porcupine dress for my son

My son goes to his play School now, and they have a talent show sort of concert on the 13th this month.

Everything is set ready for the show, except a dress for him to display as a porcupine. I have no idea, and the tailors around me are extremely busy for the seasonal dress making. So, not accepting this tough (and probably silly) one.

I decided to make one on my own... I am confident that I could do it. but how? need ideas... Ladies, please help me... If you can, please attach photos.

Urgent - How to make a porcupine dress for my son