I'm a fan of stuffed toys for cats so they can rake, chew and dig with their back feet on it. You can put your own hand in a safe place on the toy and engage Frilly with it. Soon he will probably attack it on his own. The toy should be about the same size he is.
That said, my own cats use a small piece of rolled up carpet the same way. I can get them started by poking a slender stick under it.