Pinch harmonic squealies

[DjangoUntrained]

Hi.
How do you make the harmonic squeals that use use at the end of a lot of your demonstrations? I cant see your thumb touching the string at all on the close up camera which I know is the standard way of doing them.

Thanks

[ASTN]

Pinch harmonics is a kind of stuff that is hard to learn and much harder to get rid of )