I was trying this and my coach said to focus on landing blind, so I don't have to worry about the handle-pass. I can't do it yet, but what I've been told is to use a soft edge, try take it straight up and wake to wake. Do a straight front roll and then when you're almost finished the roll, spin. Also its super important to have the handle right at your hip on scarecrows first.
I'd tell you to work on getting your scarecrows straight up using a soft edge, and getting them into more of a frontroll-then-180 trick before adding in the extra 180.
As I've said though, I can't do them and haven't tried in a year. This is just what I was told when I was trying them.