Help with moving jaw

I have looked and cannot find anything helpful, can someone help?
I want to make a moving jaw on a all foam, cat head.
(if possible...)

and if possible, does anyone have any tips on making a cat fursuit muzzle/face, and cheeks/neck- my fursuit heads always look like buckets!- thanks!

and does anyone know of any places to go in your fursuit (conventions) in Melbourne? i'm in year 8.

sorry for all of the questions---