I'll just get right into it.
You will have to find a good sized dinosaw at a 2 dolar shop somewhere, these ones i found at a local 2 dolar shop, bought 4 of them for around 10 bux.
Next you will have to find a "Sculpey" material, its unknown exactly to me as to what it is entirerly, all i know is that it works..
You CAN use greenstuff too if you want, i found Super Sculpey to be far cheaper though.
If there is enough interest shown towards this thread i'll upload a single timeline image of the knarlocs construction.
Note the fact that im new to Dakka Dakka as a member, and may not get things right first go