I saw a pattern somwhere... maybe in one of my magazines at home? I will have a look.
Online a quick search with the German term brought me to this beauty here. There is an instruction but it is for machine knitting. Can you adapt that for yourself?
There is a page with knitting charts for dinasaurs here: Charts
Just look for the one you want.
On the other hand: Take a simple pullover and design your own dinasaur. What do you want? A structure or color pattern?