I taught Kai rollover using a toy and had him follow it. Since you use the clicker, maybe you can click when she goes half way then try increasing the distance each time?

Bang seems to be a pretty impressive trick. It's really easy to teach too. I just say bang and the dogs lay on their side. It's really handy for grooming time too. Another one is gimme kiss. That one seems to be impressive as well and it's another easy one to teach. It's especially cute when Kai has to jump up to reach my lips.