Lighting up the lower part of your belly is another oft-quoted way of gently nudging bub head down.
Shine a flashlight on your belly from below. Put it right up to your skin and move it around a little and slooowly. You can do this in conjunction with sound (see above).
Why it might work:
See the theme? Babies are like us, and we all go toward the light. We can’t help it.