I find this exercise rather odd, because to my knowledge there are no concrete English grammar rules for how to order adjectives. There are, however, traditions for doing so, and these are so deeply entrenched that to break them sounds wrong. In the book The Elements of Eloquence: How to Turn the Perfect English Phrase, Mark Forsyth writes:
[A]djectives in English absolutely have to be in this order: opinion-size-age-shape-colour-origin-material-purpose Noun. So you can have a lovely little old rectangular green French silver whittling knife. But if you mess with that order in the slightest, you’ll sound like a maniac.
You can flout these customs, as a young J.R.R. Tolkien did with his story about a green great dragon, and despite what the creator of the exercise seems to believe, there are no official protocols that forbid you from doing so. But if you want to appease whoever assigned this to you, you should probably abide by Forsyth's advice.
