Alex .. the tool is pretty simple .. its not much more than x2 allen head bolts on a plate which bolts to the head .
If you pop out a green bung on the back of the head youll see the hole / recess in the camshaft .. you just need to find an allen bolt to fit it .. allen bolts have a round head .
Then a plate you can attatch them to.
All you are trying to do is hold the cams in place when you remove the cover .
Picture is from the manual .. there are probably more images there if it helps .
If you pop out a green bung on the back of the head youll see the hole / recess in the camshaft .. you just need to find an allen bolt to fit it .. allen bolts have a round head .
Then a plate you can attatch them to.
All you are trying to do is hold the cams in place when you remove the cover .
Picture is from the manual .. there are probably more images there if it helps .